WorldWideScience

Sample records for access mri system

  1. Posture-Dependent Human 3He Lung Imaging in an Open Access MRI System: Initial Results

    CERN Document Server

    Tsai, L L; Li, C -H; Rosen, M S; Patz, S; Walsworth, R L

    2007-01-01

    The human lung and its functions are extremely sensitive to orientation and posture, and debate continues as to the role of gravity and the surrounding anatomy in determining lung function and heterogeneity of perfusion and ventilation. However, study of these effects is difficult. The conventional high-field magnets used for most hyperpolarized 3He MRI of the human lung, and most other common radiological imaging modalities including PET and CT, restrict subjects to lying horizontally, minimizing most gravitational effects. In this paper, we briefly review the motivation for posture-dependent studies of human lung function, and present initial imaging results of human lungs in the supine and vertical body orientations using inhaled hyperpolarized 3He gas and an open-access MRI instrument. The open geometry of this MRI system features a "walk-in" capability that permits subjects to be imaged in vertical and horizontal positions, and potentially allows for complete rotation of the orientation of the imaging su...

  2. Open-Access, Low-Magnetic-Field MRI System for Lung Research

    Science.gov (United States)

    Mair, Ross W.; Rosen, Matthew S.; Tsai, Leo L.; Walsworth, Ronald L.; Hrovat, Mirko I.; Patz, Samuel; Ruset, Iullian C.; Hersman, F. William

    2009-01-01

    An open-access magnetic resonance imaging (MRI) system is being developed for use in research on orientational/gravitational effects on lung physiology and function. The open-access geometry enables study of human subjects in diverse orientations. This system operates at a magnetic flux density, considerably smaller than the flux densities of typical other MRI systems, that can be generated by resistive electromagnet coils (instead of the more-expensive superconducting coils of the other systems). The human subject inhales air containing He-3 or Xe-129 atoms, the nuclear spins of which have been polarized by use of a laser beam to obtain a magnetic resonance that enables high-resolution gas space imaging at the low applied magnetic field. The system includes a bi-planar, constant-current, four-coil electromagnet assembly and associated electronic circuitry to apply a static magnetic field of 6.5 mT throughout the lung volume; planar coils and associated circuitry to apply a pulsed magnetic-field-gradient for each spatial dimension; a single, detachable radio-frequency coil and associated circuitry for inducing and detecting MRI signals; a table for supporting a horizontal subject; and electromagnetic shielding surrounding the electromagnet coils.

  3. OGIS Access System

    Data.gov (United States)

    National Archives and Records Administration — The OGIS Access System (OAS) provides case management, stakeholder collaboration, and public communications activities including a web presence via a web portal.

  4. ACCESS Pointing Control System

    Science.gov (United States)

    Brugarolas, Paul; Alexander, James; Trauger, John; Moody, Dwight; Egerman, Robert; Vallone, Phillip; Elias, Jason; Hejal, Reem; Camelo, Vanessa; Bronowicki, Allen; O'Connor, David; Partrick, Richard; Orzechowski, Pawel; Spitter, Connie; Lillie, Chuck

    2010-01-01

    ACCESS (Actively-Corrected Coronograph for Exoplanet System Studies) was one of four medium-class exoplanet concepts selected for the NASA Astrophysics Strategic Mission Concept Study (ASMCS) program in 2008/2009. The ACCESS study evaluated four major coronograph concepts under a common space observatory. This paper describes the high precision pointing control system (PCS) baselined for this observatory.

  5. Towards Accessible Search Systems

    NARCIS (Netherlands)

    Serdyukov, Pavel; Hiemstra, Djoerd; Ruthven, Ian

    2010-01-01

    The SIGIR workshop Towards Accessible Search Systems was the first workshop in the field to raise the discussion on how to make search engines accessible for different types of users. We report on the results of the workshop that was held on 23 July 2010 in conjunction with the 33rd Annual ACM SIGIR

  6. Central nervous system tuberculosis: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kioumehr, F.; Dadsetan, M.R.; Rooholamini, S.A.; Au, A.

    1994-02-01

    The MRI findings of 18 proven cases of central nervous system (CNS) tuberculosis were reviewed; 10 patients were seropositive for HIV. All had medical, laboratory, or surgical proof of CNS tuberculosis. Eleven patients had meningitis, of whom two also had arachnoiditis. Five patients had focal intra-axial tuberculomas: four brain masses and one an intramedullary spinal lesion. Two patients had focal extra-axial tuberculomas: one in the pontine cistern, and one in the spine. In all 11 patients with meningitis MRI showed diffuse, thick, meningeal enhancement. All intraparenchymal tuberculomas showed low signal intensity on T2-weighted images and ring or nodular enhancement. The extra-axial tuberculomas had areas isointense or hypointense relative to normal brain and spinal cord on T2-weighted images. Although tuberculous meningitis cannot be differentiated from other meningitides on the basis of MR findings, intraparenchymal tuberculomas show characteristic T2 shortening, not found in most other space-occupying lesions. In the appropriate clinical setting, tuberculoma should be considered. (orig.)

  7. MRI of central nervous system anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Izawa, M.; Oikawa, A.; Matoba, A.

    1987-05-01

    MRI was very useful in the evaluation of congenital anomalies of central nervous system as well as other nervous system disease with three-dimensional spatial resolution. We had experienced MRI of central nervous system anomalies, demonstrated characterisitic findings in each anomaly. MRI is useful to observe the coronal, horizontal and sagittal images of the brain and spinal cord in order to discuss the etiological mechanisms of spinal dysraphysm and its associated anomalies. In case of spina bifida cystica MRI was available to decide operative indication for radical operation and tetherd cord developed from postoperative scar or accompanied intraspinal lesions.

  8. MRI of the Musculoskeletal System

    Science.gov (United States)

    ... receive injections of gadolinium contrast material except when absolutely necessary for medical treatment. See the Safety page ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ...

  9. Evaluation of MRI issues for an access port with a radiofrequency identification (RFID) tag.

    Science.gov (United States)

    Titterington, Blake; Shellock, Frank G

    2013-10-01

    A medical implant that contains metal, such as an RFID tag, must undergo proper MRI testing to ensure patient safety and to determine that the function of the RFID tag is not compromised by exposure to MRI conditions. Therefore, the objective of this investigation was to assess MRI issues for a new access port that incorporates an RFID tag. Samples of the access port with an RFID tag (Medcomp Power Injectable Port with CertainID; Medcomp, Harleysville, PA) were evaluated using standard protocols to assess magnetic field interactions (translational attraction and torque; 3-T), MRI-related heating (3-T), artifacts (3-T), and functional changes associated with different MRI conditions (nine samples, exposed to different MRI conditions at 1.5-T and 3-T). Magnetic field interactions were not substantial and will pose no hazards to patients. MRI-related heating was minimal (highest temperature change, 1.7°C; background temperature rise, 1.6°C). Artifacts were moderate in size in relation to the device. Exposures to MRI conditions at 1.5-T and 3-T did not alter or damage the functional aspects of the RFID tag. Based on the findings of the test, this new access port with an RFID tag is acceptable (or, MR conditional, using current MRI labeling terminology) for patients undergoing MRI examinations at 1.5-T/64-MHz and 3-T/128-MHz. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Computer Security Systems Enable Access.

    Science.gov (United States)

    Riggen, Gary

    1989-01-01

    A good security system enables access and protects information from damage or tampering, but the most important aspects of a security system aren't technical. A security procedures manual addresses the human element of computer security. (MLW)

  11. Automated Computer Access Request System

    Science.gov (United States)

    Snook, Bryan E.

    2010-01-01

    The Automated Computer Access Request (AutoCAR) system is a Web-based account provisioning application that replaces the time-consuming paper-based computer-access request process at Johnson Space Center (JSC). Auto- CAR combines rules-based and role-based functionality in one application to provide a centralized system that is easily and widely accessible. The system features a work-flow engine that facilitates request routing, a user registration directory containing contact information and user metadata, an access request submission and tracking process, and a system administrator account management component. This provides full, end-to-end disposition approval chain accountability from the moment a request is submitted. By blending both rules-based and rolebased functionality, AutoCAR has the flexibility to route requests based on a user s nationality, JSC affiliation status, and other export-control requirements, while ensuring a user s request is addressed by either a primary or backup approver. All user accounts that are tracked in AutoCAR are recorded and mapped to the native operating system schema on the target platform where user accounts reside. This allows for future extensibility for supporting creation, deletion, and account management directly on the target platforms by way of AutoCAR. The system s directory-based lookup and day-today change analysis of directory information determines personnel moves, deletions, and additions, and automatically notifies a user via e-mail to revalidate his/her account access as a result of such changes. AutoCAR is a Microsoft classic active server page (ASP) application hosted on a Microsoft Internet Information Server (IIS).

  12. Remotely Accessible Management System (RAMS).

    Science.gov (United States)

    Wood, Rex

    Oakland Schools, an Intermediate School District for Administration, operates a Remotely Accessible Management System (RAMS). RAMS is composed of over 100 computer programs, each of which performs procedures on the files of the 28 local school districts comprising the constituency of Oakland Schools. This regional service agency covers 900 square…

  13. An MRI system for imaging neonates in the NICU: initial feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Tkach, Jean A.; Loew, Wolfgang; Pratt, Ron G.; Daniels, Barret R.; Giaquinto, Randy O.; Winter, Patrick M.; Li, Yu; Dumoulin, Charles L. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Department of Radiology, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Hillman, Noah H.; Jobe, Alan H.; Kallapur, Suhas G.; Merhar, Stephanie L.; Ikegami, Machiko; Whitsett, Jeffrey A. [Perinatal Institute, Cincinnati Children' s Hospital Medical Center, Division of Neonatology and Pulmonary Biology, Cincinnati, OH (United States); Kline-Fath, Beth M. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2012-11-15

    Transporting premature infants from a neonatal intensive care unit (NICU) to a radiology department for MRI has medical risks and logistical challenges. To develop a small 1.5-T MRI system for neonatal imaging that can be easily installed in the NICU and to evaluate its performance using a sheep model of human prematurity. A 1.5-T MRI system designed for orthopedic use was adapted for neonatal imaging. The system was used for MRI examinations of the brain, chest and abdomen in 12 premature lambs during the first hours of life. Spin-echo, fast spin-echo and gradient-echo MR images were evaluated by two pediatric radiologists. All animals remained physiologically stable throughout the imaging sessions. Animals were imaged at two or three time points. Seven brain MRI examinations were performed in seven different animals, 23 chest examinations in 12 animals and 19 abdominal examinations in 11 animals. At each anatomical location, high-quality images demonstrating good spatial resolution, signal-to-noise ratio and tissue contrast were routinely obtained within 30 min using standard clinical protocols. Our preliminary experience demonstrates the feasibility and potential of the neonatal MRI system to provide state-of-the-art MRI capabilities within the NICU. Advantages include overall reduced cost and site demands, lower acoustic noise, improved ease of access and reduced medical risk to the neonate. (orig.)

  14. Radio access selection in multi-radio access systems

    NARCIS (Netherlands)

    Jorgušeski, L.; Litjens, R.; Zhiyi, C.; Nikookar, H.

    2007-01-01

    Future wireless access systems will be characterized by their heterogeneity from technological point of view. It is envisaged that in certain areas end-users will have a choice between various radio accesses (RAs) such as e.g. classical cellular networks (GSM, UMTS, WiMAX, etc), WLAN hot-spots, or o

  15. Pharmacological MRI (phMRI) of the Human Central Nervous System.

    Science.gov (United States)

    Lanfermann, H; Schindler, C; Jordan, J; Krug, N; Raab, P

    2015-10-01

    Pharmacological magnetic resonance imaging (phMRI) of the central nervous system (CNS) addresses the increasing demands in the biopharma industry for new methods that can accurately predict, as early as possible, whether novel CNS agents will be effective and safe. Imaging of physiological and molecular-level function can provide a more direct measure of a drug mechanism of action, enabling more predictive measures of drug activity. The availability of phMRI of the nervous system within the professional infrastructure of the Clinical Research Center (CRC) Hannover as proof of concept center ensures that advances in basic science progress swiftly into benefits for patients. Advanced standardized MRI techniques including quantitative MRI, kurtosis determination, functional MRI, and spectroscopic imaging of the entire brain are necessary for phMRI. As a result, MR scanners will evolve into high-precision measuring instruments for assessment of desirable and undesirable effects of drugs as the basic precondition for individually tailored therapy. The CRC's Imaging Unit with high-end large-scale equipment will allow the following unique opportunities: for example, identification of MR-based biomarkers to assess the effect of drugs (surrogate parameters), establishment of normal levels and reference ranges for MRI-based biomarkers, evaluation of the most relevant MRI sequences for drug monitoring in outpatient care. Another very important prerequisite for phMRI is the MHH Core Facility as the scientific and operational study unit of the CRC partner Hannover Medical School. This unit is responsible for the study coordination, conduction, complete study logistics, administration, and application of the quality assurance system based on required industry standards.

  16. Design and performance from an integrated PET/MRI system for small animals.

    Science.gov (United States)

    Yamamoto, Seiichi; Imaizumi, Masao; Kanai, Yasukazu; Tatsumi, Mitsuaki; Aoki, Masaaki; Sugiyama, Eiji; Kawakami, Makoto; Shimosegawa, Eku; Hatazawa, Jun

    2010-02-01

    Although simultaneous measurements of PET and magnetic resonance imaging (MRI) can provide interesting results in molecular imaging research, most of the combined systems are huge and animal handling in the system is not easy. To minimize these problems, we developed a compact integrated PET/MRI (iPET/MRI) system for small animals. For the iPET/MRI system, a new MR-compatible PET and a permanent magnet open MRI were designed. In the MRI, a tunnel is opened at the yoke of the magnet. The position-sensitive photo-multiplier tubes (PSPMTs) of the MR-compatible PET are positioned at the back of the yoke where the magnetic field is sufficiently low. The scintillators for the PET system are positioned at the center of the MRI magnets, and the direction of the scintillation photons is changed by slanted light guides, and they are fed to the PSPMTs by 75 cm long optical fiber bundles. The PET detectors employed two types of LGSO crystals (1.9 mm x 2.2 mm x 6 mm and 7 mm) with different decay times (33 and 43 ns) for depth of interaction detection. Sixteen optical fiber-based block detectors are arranged in a 112 mm diameter ring. The transaxial field-of-view (FOV) of the PET system is ~80 mm, and the axial FOV is 21 mm which can be enlarged by the axial motion of the PET detector ring during MRI acquisition. The transaxial and axial resolutions at the center of the PET system was 2.9 and 2.4 mm FWHM, respectively. The absolute sensitivity was 1.5% at the center of the axial FOV. Phantom images revealed no artifact in either the PET or MRI images. We successfully obtained simultaneously measured small animal images using the iPET/MRI system. The open geometry of the developed iPET/ MRI facilitates easy accessibility to the subject. The iPET/ MRI system appears to be a promising tool for molecular imaging research.

  17. Implementation of Flexible Access System

    Science.gov (United States)

    Wu, Chen-Hsiang; Peng, Jan-Wen; Shao, Shou-Kuo; Chen, Tzooming E.; Chen, Shih Chang; Lee, Meng-Shu; Yen, K.-Y.; Chen, Tsung-Mao; Wang, Ching Sheu; Tu, Yuan-Kuang

    1998-06-01

    In this paper we present the architecture, operation, and the implementation of a prototype system, flexible access system (FAS), developed by CHT T.L. for FITL applications. FAS adopts fiber to the curb (FTTC) topology and provides POTS, ISDN BRA, and T1 services. The system consists of three main parts, namely, fiber central office terminal (FCOT) at switch side, fiber nodes (FN) at customer side, and a monitor station. FCOT and FNs are connected through an STM-1 fiber distribution ring. The hardware structure and the operation principle for each module are described. FAS contains the mux-demux module, POTS, ISDN, and T1 central office/customer service modules, operation modules, and power module. In the design, each central office service module in FCOT simulates as a CPE to terminate signals from switch, and will separate the data and signaling and map them into DS1 format. Mux/demux module will add/drop these DS1, put the operation information in data communication channel (DCC), and convert them to STM-1 optical link. Each customer service module in FN simulates switch line cart to regenerate the signal for customers. The prototype system implementation confirms the benefits of introducing SDH add/drop technologies to FITL system to provide basic telecommunication services. The design experience reveals that the clock synchronization method and noise reduction technique can significantly influence the performance in such a system. The test results that demonstrate and verify the designed functionality and the service quality of the prototype system will be presented.

  18. Long-term vascular access ports as a means of sedative administration in a rodent fMRI survival model.

    Science.gov (United States)

    Hettinger, Patrick C; Li, Rupeng; Yan, Ji-Geng; Matloub, Hani S; Cho, Younghoon R; Pawela, Christopher P; Rowe, Daniel B; Hyde, James S

    2011-09-15

    The purpose of this study is to develop a rodent functional magnetic resonance imaging (fMRI) survival model with the use of heparin-coated vascular access devices. Such a model would ease the administration of sedative agents, reduce the number of animals required in survival experiments and eliminate animal-to-animal variability seen in previous designs. Seven male Sprague-Dawley rats underwent surgical placement of an MRI-compatible vascular access port, followed by implantable electrode placement on the right median nerve. Functional MRI during nerve stimulation and resting-state functional connectivity MRI (fcMRI) were performed at times 0, 2, 4, 8 and 12 weeks postoperatively using a 9.4T scanner. Anesthesia was maintained using intravenous dexmedetomidine and reversed using atipamezole. There were no fatalities or infectious complications during this study. All vascular access ports remained patent. Blood oxygen level dependent (BOLD) activation by electrical stimulation of the median nerve using implanted electrodes was seen within the forelimb sensory region (S1FL) for all animals at all time points. The number of activated voxels decreased at time points 4 and 8 weeks, returning to a normal level at 12 weeks, which is attributed to scar tissue formation and resolution around the embedded electrode. The applications of this experiment extend far beyond the scope of peripheral nerve experimentation. These vascular access ports can be applied to any survival MRI study requiring repeated medication administration, intravenous contrast, or blood sampling.

  19. Primary care direct access MRI for the investigation of chronic headache

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, T.R., E-mail: timt@nhs.net [Queens Medical Centre, Nottingham (United Kingdom); Evangelou, N. [Queens Medical Centre, Nottingham (United Kingdom); Porter, H. [Nottingham Cripps Health Centre, Nottingham (United Kingdom); Lenthall, R. [Queens Medical Centre, Nottingham (United Kingdom)

    2012-01-15

    Aim: To assess the efficacy of a primary-care imaging pathway for neurology outpatients, from inception to deployment, compared with traditional outpatient referral. Materials and methods: After local agreement, guidelines were generated providing pathways for diagnosis and treatment of common causes of headache, highlighting 'red-flag' features requiring urgent neurology referral, and selecting patients for direct magnetic resonance imaging (MRI) referral. In addition, reports were clarified and standardized. To evaluate the efficacy of the access pathway, a retrospective sequential review of 100 MRI investigations was performed comparing general practitioner (GP) referral, with traditional neurology referral plus imaging, acquired before the pathway started. Results: No statistically significant difference in rates of major abnormalities, incidental findings or ischaemic lesions were identified between the two cohorts. Reported patient satisfaction was high, with a cost reduction for groups using the pathway. Conclusion: The findings of the present study suggest that a defined access pathway for imaging to investigate chronic headache can be deployed appropriately in a primary-care setting.

  20. A new access scheme in OFDMA systems

    Institute of Scientific and Technical Information of China (English)

    GU Xue-lin; YAN Wei; TIAN Hui; ZHANG Ping

    2006-01-01

    This article presents a dynamic random access scheme for orthogonal frequency division multiple access (OFDMA) systems. The key features of the proposed scheme are:it is a combination of both the distributed and the centralized schemes, it can accommodate several delay sensitivity classes,and it can adjust the number of random access channels in a media access control (MAC) frame and the access probability according to the outcome of Mobile Terminals access attempts in previous MAC frames. For floating populated packet-based networks, the proposed scheme possibly leads to high average user satisfaction.

  1. Interference between PET and MRI sub-systems in a silicon-photomultiplier-based PET/MRI system.

    Science.gov (United States)

    Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Aoki, Masaaki; Sugiyama, Eiji; Watabe, Tadashi; Imaizumi, Masao; Shimosegawa, Eku; Hatazawa, Jun

    2011-07-07

    The silicon-photomultiplier (Si-PM) is a promising photodetector, especially for integrated PET/MRI systems, due to its small size, high gain, and low sensitivity to static magnetic fields. The major problem using a Si-PM-based PET system within the MRI system is the interference between the PET and MRI units. We measured the interference by combining a Si-PM-based PET system with a permanent-magnet MRI system. When the RF signal-induced pulse height exceeded the lower energy threshold level of the PET system, interference between the Si-PM-based PET system and MRI system was detected. The prompt as well as the delayed coincidence count rates of the Si-PM-based PET system increased significantly. These noise counts produced severe artifacts on the reconstructed images of the Si-PM-based PET system. In terms of the effect of the Si-PM-based PET system on the MRI system, although no susceptibility artifact was observed on the MR images, electronic noise from the PET detector ring was detected by the RF coil and reduced the signal-to-noise ratio (S/N) of the MR images. The S/N degradation of the MR images was reduced when the distance between the RF coil and the Si-PM-based PET system was increased. We conclude that reducing the interference between the PET and MRI systems is essential for achieving the optimum performance of integrated Si-PM PET/MRI systems.

  2. MRI

    Science.gov (United States)

    MRI does not use ionizing radiation. No side effects from the magnetic fields and radio waves have been reported. The most common type of contrast (dye) used is gadolinium. It is very safe. Allergic reactions rarely ...

  3. Preliminary Evaluation of a MRI-compatible Modular Robotic System for MRI-guided Prostate Interventions.

    Science.gov (United States)

    Song, Sang-Eun; Cho, Nathan; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare; Fichtinger, Gabor; Iordachita, Iulian

    2010-09-26

    Magnetic Resonance Imaging (MRI) guided robotic interventions have been introduced in order to advance prostate cancer detection and treatment. To overcome problems of such robotic interventions, we have been developing a pneumatically actuated MRI-compatible modular robotic system for MRI-guided transperineal prostate intervention and its interventional procedure. For system evaluation, a series of experiments have been conducted and this paper reports a needle insertion experiment using prostate phantom and patient mockup trials. The needle insertion experiment resulted in noticeable consistent error in one direction, which we will investigate further. Nonetheless, patient mockup experiences suggest that the modular robotic system and its interventional procedure are well integrated and implemented in clinical environment.

  4. Easy Access: Auditing the System Network

    Science.gov (United States)

    Wiech, Dean

    2013-01-01

    In today's electronic learning environment, access to appropriate systems and data is of the utmost importance to students, faculty, and staff. Without proper access to the school's internal systems, teachers could be prevented from logging on to an online learning system and students might be unable to submit course work to an online…

  5. Development of an outdoor MRI system for measuring flow in a living tree

    Science.gov (United States)

    Nagata, Akiyoshi; Kose, Katsumi; Terada, Yasuhiko

    2016-04-01

    An outdoor MRI system for noninvasive, long-term measurements of sap flow in a living tree in its natural environment has been developed. An open-access, 0.2 T permanent magnet with a 160 mm gap was combined with a radiofrequency probe, planar gradient coils, electromagnetic shielding, several electrical units, and a waterproofing box. Two-dimensional cross-sectional images were acquired for a ring-porous tree, and the anatomical structures, including xylem and phloem, were identified. The MRI flow measurements demonstrated the diurnal changes in flow velocity in the stem on a per-pixel basis. These results demonstrate that our outdoor MRI system is a powerful tool for studies of water transport in outdoor trees.

  6. Large Field-of-View Real-Time MRI With a 32-Channel System

    OpenAIRE

    2004-01-01

    The emergence of parallel MRI techniques and new applications for real-time interactive MRI underscores the need to evaluate performance gained by increasing the capability of MRI phased-array systems beyond the standard four to eight high-bandwidth channels. Therefore, to explore the advantages of highly parallel MRI a 32-channel 1.5 T MRI system and 32-element torso phased arrays were designed and constructed for real-time interactive MRI. The system was assembled from multiple synchronized...

  7. Access control and personal identification systems

    CERN Document Server

    Bowers, Dan M

    1988-01-01

    Access Control and Personal Identification Systems provides an education in the field of access control and personal identification systems, which is essential in selecting the appropriate equipment, dealing intelligently with vendors in purchases of the equipment, and integrating the equipment into a total effective system. Access control devices and systems comprise an important part of almost every security system, but are seldom the sole source of security. In order for the goals of the total system to be met, the other portions of the security system must also be well planned and executed

  8. Grain quality of drought tolerant accessions within the MRI Zemun Polje maize germplasm collection

    Energy Technology Data Exchange (ETDEWEB)

    Vancetovic, J.; Ignjatovic-Micic, D.; Bozinovic, S.; Babbic, M.; Filipovic, M.; Grcic, N.; Andjelkovic, V.

    2014-06-01

    Maize Research Institute Zemun Polje (MRI) gene bank created an elite drought tolerant core collection of 40 accessions, based on field trials and general combining ability with inbred lines from the main heterotic groups (Lancaster, Iowa Stiff Stalk Synthetic . BSSS and Iodent). A total of seven genetic groups were identified. Seven accessions showed good combining abilities with three testers from chosen heterotic groups, thus forming a distinctive genetic group (Unknown). In the present research, accessions with drought tolerance were also analyzed for grain quality, as these two traits are becoming highly important due to global warming and population growth. Kernel macronutrients contents (oil, protein and starch) were determined using Near Infrared Spectroscopy (NIR). Oil, protein and starch contents were significantly higher in introduced populations than in landraces for 0.43%, 0.12% and 0.85%, respectively (p < 0.01). The greatest progress from the selection based on the expected genetic gain ({Delta}G) for 5% selection intensity would be obtained for oil (14.74%) followed by protein (10.14%). Landraces showed the least potential for the grain quality improvement due to the lowest expected {Delta}G for the three macronutrients. The differences between macronutrient content among genetic groups defined them as potentially favourable sources for a specific trait. According to {Delta}G values, the greatest progress in breeding would be accomplished for increased oil content with accessions from the Unknown group. Identification of the accessions with several favorable traits is valuable for simultaneous breeding for drought tolerance and grain quality. (Author)

  9. Grain quality of drought tolerant accessions within the MRI Zemun Polje maize germplasm collection

    Directory of Open Access Journals (Sweden)

    Jelena Vančetović

    2014-01-01

    Full Text Available Maize Research Institute Zemun Polje (MRI gene bank created an elite drought tolerant core collection of 40 accessions, based on field trials and general combining ability with inbred lines from the main heterotic groups (Lancaster, Iowa Stiff Stalk Synthetic - BSSS and Iodent. A total of seven genetic groups were identified. Seven accessions showed good combining abilities with three testers from chosen heterotic groups, thus forming a dinstinctive genetic group (Unknown. In the present research, accessions with drought tolerance were also analyzed for grain quality, as these two traits are becoming highly important due to global warming and population growth. Kernel macronutrients contents (oil, protein and starch were determined using Near Infrared Spectroscopy (NIR. Oil, protein and starch contents were significantly higher in introduced populations than in landraces for 0.43%, 0.12% and 0.85%, respectively (p<0.01. The greatest progress from the selection based on the expected genetic gain (ΔG for 5% selection intensity would be obtained for oil (14.74% followed by protein (10.14%. Landraces showed the least potential for the grain quality improvement due to the lowest expected ΔG for the three macronutrients. The differences between macronutrient content among genetic groups defined them as potentially favourable sources for a specific trait. According to ΔG values, the greatest progress in breeding would be accomplished for increased oil content with accessions from the Unknown group. Identification of the accessions with several favorable traits is valuable for simultaneous breeding for drought tolerance and grain quality.

  10. The LHC access system LACS and LASS

    CERN Document Server

    Ninin, P

    2005-01-01

    The LHC complex is divided into a number of zones with different levels of access controls.Inside the interlocked areas, the personnel protection is ensured by the LHC Access System.The system is made of two parts:the LHC Access Safety System and the LHC Access Control System. During machine operation,the LHC Access Safety System ensures the collective protection of the personnel against the radiation hazards arising from the operation of the accelerator by interlocking the LHC key safety elements. When the beams are off, the LHC Access Control System regulates the access to the accelerator and its many subsystems.It allows a remote, local or automatic operation of the access control equipment which verifies and identifies all users entering the controlled areas.The global architecture of the LHC Access System is now designed and is being validated to ensure that it meets the safety requirements for operation of the LHC.A pilot installation will be tested in the summer 2005 to validate the concept with the us...

  11. CDC STATE System Tobacco Legislation - Youth Access

    Data.gov (United States)

    U.S. Department of Health & Human Services — 1995-2016. Centers for Disease Control and Prevention (CDC). State Tobacco Activities Tracking and Evaluation (STATE) System. Legislation—Youth Access. The STATE...

  12. A new MRI grading system for chondromalacia patellae.

    Science.gov (United States)

    Özgen, Ali; Taşdelen, Neslihan; Fırat, Zeynep

    2017-04-01

    Background Chondromalacia patellae is a very common disorder. Although magnetic resonance imaging (MRI) is widely used to investigate patellar cartilage lesions, there is no descriptive MRI-based grading system for chondromalacia patellae. Purpose To propose a new MRI grading system for chondromalacia patellae with corresponding high resolution images which might be useful in precisely reporting and comparing knee examinations in routine daily practice and used in predicting natural course and clinical outcome of the patellar cartilage lesions. Material and Methods High resolution fat-saturated proton density (FS PD) images in the axial plane with corresponding T2 mapping images were reviewed. A detailed MRI grading system covering the deficiencies of the existing gradings has been set and presented on these images. Two experienced observers blinded to clinical data examined 44 knee MR images and evaluated patellar cartilage changes according to the proposed grading system. Inter- and intra-rater validity testing using kappa statistics were calculated. Results A descriptive and detailed grading system with corresponding FS PD and T2 mapping images has been presented. Inter-rater agreement was 0.80 (95% confidence interval [CI], 0.71-0.89). Intra-rater agreements were 0.83 (95% CI, 0.74-0.91) for observer A and 0.79 (95% CI, 0.70-0.88) for observer B (k-values). Conclusion We present a new MRI grading system for chondromalacia patellae with corresponding images and good inter- and intra-rater agreement which might be useful in reporting and comparing knee MRI examinations in daily practice and may also have the potential for using more precisely predicting prognosis and clinical outcome of the patients.

  13. Interventional CT and MRI: a challenge for safety and cost reduction in the health care system

    Science.gov (United States)

    Groenemeyer, Dietrich H.; Seibel, Rainer M.

    1995-10-01

    For increasing safety in guidance techniques of endoscopes and instruments, fast radiologic imaging should be integrated. Magnetic resonance imaging (MRI), computer tomography (CT) and electron beam tomography (EBT) scanners permit transparency of the operative field; CT and EBT can be combined with fluoroscopy and ultrasound units. MRI avoids x ray exposure, but entails the possibility for 3 D localization. Open access and keyhole imaging allows nearly real time guidance of instruments. Combining minimally invasive techniques using endoscopes and tomographic guidance these technologies improve surgical access and reduce complications. This offers a safe access into the body and leads to the new field of interventional and surgical tomography. Important cost reduction for health care systems is possible, especially in the outpatient treatment of common diseases like disk herniation, back and tumor pain, metastasis, or arteriosclerosis. For realizing a long term cost reduction effect, these techniques have to be integrated in a quality management combining prevention, modern diagnosis, minimal access techniques and, if necessary, hospital stay with maximal access treatments as well as rehabilitation and secondary/tertiary prevention.

  14. Transperineal prostate biopsy with ECHO-MRI fusion. Biopsee system. Initial experience.

    Science.gov (United States)

    Romero-Selas, E; Cuadros, V; Montáns, J; Sánchez, E; López-Alcorocho, J M; Gómez-Sancha, F

    2016-06-01

    The aim of this study is to present our initial experience with the stereotactic echo-MRI fusion system for diagnosing prostate cancer. Between September 2014 and January 2015, we performed 50 prostate biopsies using the stereotactic echo-MRI fusion system. The 3-Tesla multiparameter MR images were superimposed using this image fusion system on 3D echo images obtained with the Biopsee system for the exact locating of areas suspected of prostate cancer. The lesions were classified using the Prostate Imaging Report and Date System. We assessed a total of 50 patients, with a mean age of 63 years (range, 45-79), a mean prostate-specific antigen level of 8 ng/mL (range, 1.9-20) and a mean prostate volume of 52mL (range, 12-118). Prostate cancer was diagnosed in 69% of the patients and intraepithelial neoplasia in 6%. The results of the biopsy were negative for 24% of the patients. The results of the biopsy and MRI were in agreement for 62% of the patients; however, 46% also had a tumour outside of the suspicious lesion. We diagnosed 46% anterior tumours and 33% apical tumours. One patient had a haematuria, another had a haematoma and a third had acute urine retention. Multiparametric prostatic MRI helps identify prostate lesions suggestive of cancer. The Biopsee echo-MRI fusion system provides for guided biopsy and increases the diagnostic performance, reducing the false negatives of classical biopsies and increasing the diagnosis of anterior tumours. Transperineal access minimises the risk of prostatic infection and sepsis. Copyright © 2015 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. Perfusion MRI in neuro-psychiatric systemic lupus erthemathosus.

    NARCIS (Netherlands)

    Emmer, B.J.; Osch, M.J. van; Wu, O.; Steup-Beekman, G.M.; Steens, S.; Huizinga, T.W.J.; Buchem, M.A. van; Grond, J. van der

    2010-01-01

    PURPOSE: To use perfusion weighted MR to quantify any perfusion abnormalities and to determine their contribution to neuropsychiatric (NP) involvement in systemic lupus erythematosus (SLE). MATERIALS AND METHODS: We applied dynamic susceptibility contrast (DSC) perfusion MRI in 15 active NPSLE, 26 i

  16. Distributed Access View Integrated Database (DAVID) system

    Science.gov (United States)

    Jacobs, Barry E.

    1991-01-01

    The Distributed Access View Integrated Database (DAVID) System, which was adopted by the Astrophysics Division for their Astrophysics Data System, is a solution to the system heterogeneity problem. The heterogeneous components of the Astrophysics problem is outlined. The Library and Library Consortium levels of the DAVID approach are described. The 'books' and 'kits' level is discussed. The Universal Object Typer Management System level is described. The relation of the DAVID project with the Small Business Innovative Research (SBIR) program is explained.

  17. Linear systems analysis of the fMRI signal.

    Science.gov (United States)

    Boynton, Geoffrey M; Engel, Stephen A; Heeger, David J

    2012-08-15

    In 1995 when we began our investigations of the human visual system using fMRI, little was known about the temporal properties of the fMRI signal. Before we felt comfortable making quantitative estimates of neuronal responses with this new technique, we decided to first conduct a basic study of how the time-course of the fMRI response varied with stimulus timing and strength. The results ended up showing strong evidence that to a first approximation the hemodynamic transformation was linear in time. This was both important and remarkable: important because nearly all fMRI data analysis techniques assume or require linearity, and remarkable because the physiological basis of the hemodynamic transformation is so complex that we still have a far from complete understanding of it. In this paper, we provide highlights of the results of our original paper supporting the linear transform hypothesis. A reanalysis of the original data provides some interesting new insights into the published results. We also provide a detailed appendix describing of the properties and predictions of a linear system in time in the context of the transformation between neuronal responses and the BOLD signal.

  18. Access Control in Data Management Systems

    CERN Document Server

    Ferrari, Elena

    2010-01-01

    Access control is one of the fundamental services that any Data Management System should provide. Its main goal is to protect data from unauthorized read and write operations. This is particularly crucial in today's open and interconnected world, where each kind of information can be easily made available to a huge user population, and where a damage or misuse of data may have unpredictable consequences that go beyond the boundaries where data reside or have been generated. This book provides an overview of the various developments in access control for data management systems. Discretionary,

  19. Three Dimensional Modeling of an MRI Actuated Steerable Catheter System.

    Science.gov (United States)

    Liu, Taoming; Cavuşoğlu, M Cenk

    2014-01-01

    This paper presents the three dimensional kinematic modeling of a novel steerable robotic ablation catheter system. The catheter, embedded with a set of current-carrying micro-coils, is actuated by the magnetic forces generated by the magnetic field of the MRI scanner. This paper develops a 3D model of the MRI actuated steerable catheter system by using finite differences approach. For each finite segment, a quasi-static torque-deflection equilibrium equation is calculated using beam theory. By using the deflection displacements and torsion angles, the kinematic modeling of the catheter system is derived. The proposed models are evaluated by comparing the simulation results of the proposed model with the experimental results of a proof-of-concept prototype.

  20. Totally Accessible MRI A User's Guide to Principles, Technology, and Applications

    CERN Document Server

    Lipton, Michael L

    2008-01-01

    This is a practical guide that offers a lucid introduction to the principles of MRI physics. The author, recognized in the imaging community for his exceptional teaching methods and lectures, has written an easy to understand text. Each chapter explains the "why" and "how" behind MRI physics. Readers will understand how altering MRI parameters will have many different consequences for image quality and the speed in which images are generated. Practical topics, selected for their value to clinical practice, include progressive changes in key MRI parameters, imaging time, and signal to noise ratio. A wealth of high quality illustrations, complemented by concise text, enables readers to gain a thorough understanding of the subject without requiring prior in-depth knowledge

  1. Superconductors Enable Lower Cost MRI Systems

    Science.gov (United States)

    2013-01-01

    The future looks bright, light, and green, especially where aircraft are concerned. The division of NASA s Fundamental Aeronautics Program called the Subsonic Fixed Wing Project is aiming to reach new heights by 2025-2035, improving the efficiency and environmental impact of air travel by developing new capabilities for cleaner, quieter, and more fuel efficient aircraft. One of the many ways NASA plans to reach its aviation goals is by combining new aircraft configurations with an advanced turboelectric distributed propulsion (TeDP) system. Jeff Trudell, an engineer at Glenn Research Center, says, "The TeDP system consists of gas turbines generating electricity to power a large number of distributed motor-driven fans embedded into the airframe." The combined effect increases the effective bypass ratio and reduces drag to meet future goals. "While room temperature components may help reduce emissions and noise in a TeDP system, cryogenic superconducting electric motors and generators are essential to reduce fuel burn," says Trudell. Superconductors provide significantly higher current densities and smaller and lighter designs than room temperature equivalents. Superconductors are also able to conduct direct current without resistance (loss of energy) below a critical temperature and applied field. Unfortunately, alternating current (AC) losses represent the major part of the heat load and depend on the frequency of the current and applied field. A refrigeration system is necessary to remove the losses and its weight increases with decreasing temperature. In 2001, a material called magnesium diboride (MgB2) was discovered to be superconducting. The challenge, however, has been learning to manufacture MgB2 inexpensively and in long lengths to wind into large coils while meeting the application requirements.

  2. Development and Evaluation of an Actuated MRI-Compatible Robotic System for MRI-Guided Prostate Intervention

    Science.gov (United States)

    Krieger, Axel; Song, Sang-Eun; Cho, Nathan B.; Iordachita, Iulian; Guion, Peter; Fichtinger, Gabor; Whitcomb, Louis L.

    2012-01-01

    This paper reports the design, development, and magnetic resonance imaging (MRI) compatibility evaluation of an actuated transrectal prostate robot for MRI-guided needle intervention in the prostate. The robot performs actuated needle MRI-guidance with the goals of providing (i) MRI compatibility, (ii) MRI-guided needle placement with accuracy sufficient for targeting clinically significant prostate cancer foci, (iii) reducing interventional procedure times (thus increasing patient comfort and reducing opportunity for needle targeting error due to patient motion), (iv) enabling real-time MRI monitoring of interventional procedures, and (v) reducing the opportunities for error that arise in manually actuated needle placement. The design of the robot, employing piezo-ceramic-motor actuated needle guide positioning and manual needle insertion, is reported. Results of a MRI compatibility study show no reduction of MRI signal-to-noise-ratio (SNR) with the motors disabled. Enabling the motors reduces the SNR by 80% without RF shielding, but SNR is only reduced by 40% to 60% with RF shielding. The addition of radio-frequency shielding is shown to significantly reduce image SNR degradation caused by the presence of the robotic device. An accuracy study of MRI-guided biopsy needle placements in a prostate phantom is reported. The study shows an average in-plane targeting error of 2.4 mm with a maximum error of 3.7 mm. These data indicate the system’s needle targeting accuracy is similar to that obtained with a previously reported manually actuated system, and is sufficient to reliably sample clinically significant prostate cancer foci under MRI-guidance. PMID:23326181

  3. A robotic assistant system for cardiac interventions under MRI guidance

    Science.gov (United States)

    Li, Ming; Mazilu, Dumitru; Wood, Bradford J.; Horvath, Keith A.; Kapoor, Ankur

    2010-02-01

    In this paper we present a surgical assistant system for implanting prosthetic aortic valve transapically under MRI guidance, in a beating heart. The system integrates an MR imaging system, a robotic system, as well as user interfaces for a surgeon to plan the procedure and manipulate the robot. A compact robotic delivery module mounted on a robotic arm is used for delivering both balloon-expandable and self-expanding prosthesis. The system provides different user interfaces at different stages of the procedure. A compact fiducial pattern close to the volume of interest is proposed for robot registration. The image processing and the transformation recovery methods using this fiducial in MRI are presented. The registration accuracy obtained by using this compact fiducial is comparable to the larger multi-spherical marker registration method. The registration accuracy using these two methods is less than 0.62+/-0.50 deg (mean +/- std. dev.) and 0.63+/-0.72 deg (mean +/- std. dev.), respectively. We evaluated each of the components and show that they can work together to form a complete system for transapical aortic valve replacement.

  4. Semi-blind independent component analysis of fMRI based on real-time fMRI system.

    Science.gov (United States)

    Ma, Xinyue; Zhang, Hang; Zhao, Xiaojie; Yao, Li; Long, Zhiying

    2013-05-01

    Real-time functional magnetic resonance imaging (fMRI) is a type of neurofeedback tool that enables researchers to train individuals to actively gain control over their brain activation. Independent component analysis (ICA) based on data-driven model is seldom used in real-time fMRI studies due to large time cost, though it has been very popular to offline analysis of fMRI data. The feasibility of performing real-time ICA (rtICA) processing has been demonstrated by previous study. However, rtICA was only applied to analyze single-slice data rather than full-brain data. In order to improve the performance of rtICA, we proposed semi-blind real-time ICA (sb-rtICA) for our real-time fMRI system by adding regularization of certain estimated time courses using the experiment paradigm information to rtICA. Both simulated and real-time fMRI experiment were conducted to compare the two approaches. Results from simulated and real full-brain fMRI data demonstrate that sb-rtICA outperforms rtICA in robustness, computational time and spatial detection power. Moreover, in contrast to rtICA, the first component estimated by sb-rtICA tends to be the target component in more sliding windows.

  5. Science information systems: Archive, access, and retrieval

    Science.gov (United States)

    Campbell, William J.

    1991-01-01

    The objective of this research is to develop technology for the automated characterization and interactive retrieval and visualization of very large, complex scientific data sets. Technologies will be developed for the following specific areas: (1) rapidly archiving data sets; (2) automatically characterizing and labeling data in near real-time; (3) providing users with the ability to browse contents of databases efficiently and effectively; (4) providing users with the ability to access and retrieve system independent data sets electronically; and (5) automatically alerting scientists to anomalies detected in data.

  6. Decentralized energy systems for clean electricity access

    Science.gov (United States)

    Alstone, Peter; Gershenson, Dimitry; Kammen, Daniel M.

    2015-04-01

    Innovative approaches are needed to address the needs of the 1.3 billion people lacking electricity, while simultaneously transitioning to a decarbonized energy system. With particular focus on the energy needs of the underserved, we present an analytic and conceptual framework that clarifies the heterogeneous continuum of centralized on-grid electricity, autonomous mini- or community grids, and distributed, individual energy services. A historical analysis shows that the present day is a unique moment in the history of electrification where decentralized energy networks are rapidly spreading, based on super-efficient end-use appliances and low-cost photovoltaics. We document how this evolution is supported by critical and widely available information technologies, particularly mobile phones and virtual financial services. These disruptive technology systems can rapidly increase access to basic electricity services and directly inform the emerging Sustainable Development Goals for quality of life, while simultaneously driving action towards low-carbon, Earth-sustaining, inclusive energy systems.

  7. Digital Autonomous Terminal Access Communication (DATAC) system

    Science.gov (United States)

    Novacki, Stanley M., III

    1987-01-01

    In order to accommodate the increasing number of computerized subsystems aboard today's more fuel efficient aircraft, the Boeing Co. has developed the DATAC (Digital Autonomous Terminal Access Control) bus to minimize the need for point-to-point wiring to interconnect these various systems, thereby reducing total aircraft weight and maintaining an economical flight configuration. The DATAC bus is essentially a local area network providing interconnections for any of the flight management and control systems aboard the aircraft. The task of developing a Bus Monitor Unit was broken down into four subtasks: (1) providing a hardware interface between the DATAC bus and the Z8000-based microcomputer system to be used as the bus monitor; (2) establishing a communication link between the Z8000 system and a CP/M-based computer system; (3) generation of data reduction and display software to output data to the console device; and (4) development of a DATAC Terminal Simulator to facilitate testing of the hardware and software which transfer data between the DATAC's bus and the operator's console in a near real time environment. These tasks are briefly discussed.

  8. Application of Artificial Immune System Approach in MRI Classification

    Directory of Open Access Journals (Sweden)

    Gia-Hao Chang

    2008-05-01

    Full Text Available Numerous scholars have submitted the theory and research of artificial immune systems (AISs in recent years. Although AIS has been used in various fields, applying the AIS to medical images is very rare. The purpose of this study is using the clonal selection algorithm (CSA of artificial immune systems for classifying the brain MRI, and displaying a single organism image which can finally offer faster organism reference information to a doctor; hence reducing the time to ascertain large number of images, so that the doctor can diagnose the nidus more efficiently and accurately. In order to verify the feasibility and efficiency of this method, we adopt statistical theory for manifold assessment and compare with the perceptron network of double layers, FCM method. The result proves that the method of this study is both feasible and useful.

  9. Quantitative evaluation of the reticuloendothelial system function with dynamic MRI.

    Directory of Open Access Journals (Sweden)

    Ting Liu

    Full Text Available PURPOSE: To evaluate the reticuloendothelial system (RES function by real-time imaging blood clearance as well as hepatic uptake of superparamagnetic iron oxide nanoparticle (SPIO using dynamic magnetic resonance imaging (MRI with two-compartment pharmacokinetic modeling. MATERIALS AND METHODS: Kinetics of blood clearance and hepatic accumulation were recorded in young adult male 01b74 athymic nude mice by dynamic T2* weighted MRI after the injection of different doses of SPIO nanoparticles (0.5, 3 or 10 mg Fe/kg. Association parameter, Kin, dissociation parameter, Kout, and elimination constant, Ke, derived from dynamic data with two-compartment model, were used to describe active binding to Kupffer cells and extrahepatic clearance. The clodrosome and liposome were utilized to deplete macrophages and block the RES function to evaluate the capability of the kinetic parameters for investigation of macrophage function and density. RESULTS: The two-compartment model provided a good description for all data and showed a low sum squared residual for all mice (0.27±0.03. A lower Kin, a lower Kout and a lower Ke were found after clodrosome treatment, whereas a lower Kin, a higher Kout and a lower Ke were observed after liposome treatment in comparison to saline treatment (P<0.005. CONCLUSION: Dynamic SPIO-enhanced MR imaging with two-compartment modeling can provide information on RES function on both a cell number and receptor function level.

  10. Embedded systems for supporting computer accessibility.

    Science.gov (United States)

    Mulfari, Davide; Celesti, Antonio; Fazio, Maria; Villari, Massimo; Puliafito, Antonio

    2015-01-01

    Nowadays, customized AT software solutions allow their users to interact with various kinds of computer systems. Such tools are generally available on personal devices (e.g., smartphones, laptops and so on) commonly used by a person with a disability. In this paper, we investigate a way of using the aforementioned AT equipments in order to access many different devices without assistive preferences. The solution takes advantage of open source hardware and its core component consists of an affordable Linux embedded system: it grabs data coming from the assistive software, which runs on the user's personal device, then, after processing, it generates native keyboard and mouse HID commands for the target computing device controlled by the end user. This process supports any operating system available on the target machine and it requires no specialized software installation; therefore the user with a disability can rely on a single assistive tool to control a wide range of computing platforms, including conventional computers and many kinds of mobile devices, which receive input commands through the USB HID protocol.

  11. Research of user access control for networked manufacturing system

    Institute of Scientific and Technical Information of China (English)

    ZHENG Xiao-lin; LEI Yu; CHEN De-ren

    2006-01-01

    An integrated user access control method was proposed to address the issues of security and management in networked manufacturing systems (NMS).Based on the analysis of the security issues in networked manufacturing system,an integrated user access control method composed of role-based access control (RBAC),task-based access control (TBAC),relationship-driven access control (RDAC)and coalition-based access control (CBAC) was proposed,including the hierarchical user relationship model,the reference model and the process model.The elements and their relationships were defined,and the expressions of constraints authorization were given.The extensible access control markup language (XACML) was used to implement this method.This method was used in the networked manufacturing system in the Shaoxing spinning region of China.The results show that the integrated user access control method can reduce the costs of system security maintenance and management.

  12. Adapting MRI systems to propel and guide microdevices in the human blood circulatory system.

    Science.gov (United States)

    Martel, S; Mathieu, J B; Felfoul, O; Macicior, H; Beaudoin, G; Soulez, G; Yahia, L H

    2004-01-01

    Magnetic resonance imaging (MRI) systems are widely used to gather noninvasively images of the interior of the human body. This paper suggests that an MRI system can be seen beyond being just a tool for imaging purpose but one that can propel and guide special microdevices in the human body to perform specific medical tasks. More specifically, an MRI system can potentially be used to image the region of interest, propel a microdevice through the generation of magnetic gradients, determine the location of the device, compute the corrective actions through feedback control algorithms and adjust the generation of the magnetic gradients accordingly to navigate such a microdevice in a preplanned path. This paper presents an introductory description of the proposed techniques, the main issues to consider, and some preliminary data indicating the validity of this approach.

  13. Incorporating MRI structural information into bioluminescence tomography: system, heterogeneous reconstruction and in vivo quantification.

    Science.gov (United States)

    Zhang, Jun; Chen, Duofang; Liang, Jimin; Xue, Huadan; Lei, Jing; Wang, Qin; Chen, Dongmei; Meng, Ming; Jin, Zhengyu; Tian, Jie

    2014-06-01

    Combining two or more imaging modalities to provide complementary information has become commonplace in clinical practice and in preclinical and basic biomedical research. By incorporating the structural information provided by computed tomography (CT) or magnetic resonance imaging (MRI), the ill poseness nature of bioluminescence tomography (BLT) can be reduced significantly, thus improve the accuracies of reconstruction and in vivo quantification. In this paper, we present a small animal imaging system combining multi-view and multi-spectral BLT with MRI. The independent MRI-compatible optical device is placed at the end of the clinical MRI scanner. The small animal is transferred between the light tight chamber of the optical device and the animal coil of MRI via a guide rail during the experiment. After the optical imaging and MRI scanning procedures are finished, the optical images are mapped onto the MRI surface by interactive registration between boundary of optical images and silhouette of MRI. Then, incorporating the MRI structural information, a heterogeneous reconstruction algorithm based on finite element method (FEM) with L 1 normalization is used to reconstruct the position, power and region of the light source. In order to validate the feasibility of the system, we conducted experiments of nude mice model implanted with artificial light source and quantitative analysis of tumor inoculation model with MDA-231-GFP-luc. Preliminary results suggest the feasibility and effectiveness of the prototype system.

  14. Context-Based E-Health System Access Control Mechanism

    Science.gov (United States)

    Al-Neyadi, Fahed; Abawajy, Jemal H.

    E-Health systems logically demand a sufficiently fine-grained authorization policy for access control. The access to medical information should not be just role-based but should also include the contextual condition of the role to access data. In this paper, we present a mechanism to extend the standard role-based access control to incorporate contextual information for making access control decisions in e-health application. We present an architecture consisting of authorisation and context infrastructure that work cooperatively to grant access rights based on context-aware authorization policies and context information.

  15. Acoustic fMRI noise : Linear time-invariant system model

    NARCIS (Netherlands)

    Sierra, Carlos V. Rizzo; Versluis, Maarten J.; Hoogduin, Johannes M.; Duifhuis, Hendrikus (Diek)

    2008-01-01

    Functional magnetic resonance imaging (fMRI) enables sites of brain activation to be localized in human subjects. For auditory system studies, however, the acoustic noise generated by the scanner tends to interfere with the assessments of this activation. Understanding and modeling fMRI acoustic noi

  16. A Digitally Addressable Random-Access Image Selector and Random-Access Audio System.

    Science.gov (United States)

    Bitzer, Donald L.; And Others

    The requirements of PLATO IV, a computer based education system at the University of Illinois, have led to the development of an improved, digitally addressable, random access image selector and a digitally addressable, random access audio device. Both devices utilize pneumatically controlled mechanical binary adders to position the mecahnical…

  17. Campus Access Control System RFID Based

    Directory of Open Access Journals (Sweden)

    Mr. SANTHOSH S

    2012-06-01

    Full Text Available Radio frequency identification (RFID technology has helped many organizations to reduce cost. Nevertheless, there are challenges and issues associated with RFID adoption. The most common internal challenge for many organizations is justifying the investment and modification of processes. The focus of this project is to show the business value of RFID technology and its applications. The important issue is the security level of the whole campus because it needs to be carefully differentiated. Dormitories and special research laboratories should benefit from higher levels of security than any other campuses. The key to the problem is represented by the new Radio Frequency Identification (RFID which can support contactless cards with memory. The most important feature of the proposed system is the updating of access permission level at any time for the user based on the availability of that user. The data transfer from the reader to the database was done using wireless communication (RF communication. To achieve this here RF transmitter and the RF receiver is used. The data which is read by the reader is sent to the microcontroller. Then from the controller we can transfer the data to the database by using the UART module (serial communication which is inbuilt in the microcontroller through RF transmitter. RF receiver of the same frequency at the receiver end receives and then stores the data in the database. RF transmitter and Receiver – frequency for transmitting and receiving the data depends on the user as per the requirement for the application and it is based on the range of distance. For the data encoding and decoding process HCS-101 protocol is used.

  18. MRI changes in the central nervous system in a child with lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Gieron, M.A. [Dept. of Pediatrics, Univ. of South Florida, Coll. of Medicine, Tampa, FL (United States); Khoromi, S. [Dept. of Neurology, Univ. of South Florida, Coll. of Medicine, Tampa, FL (United States); Campos, A. [Dept. of Pediatrics, Univ. of South Florida, Coll. of Medicine, Tampa, FL (United States)

    1995-05-01

    We report on a 10-year-old girl with systemic lupus erythematosus who presented in status epilepticus as the only manifestation of central nervous system involvement. MRI of the brain showed diffuse gray and white matter lesions which almost completely resolved after treatment with methylprednisolone. MRI findings in this child are similar to those in adults with diffuse clinical manifestations. The study is essential in the initial evaluation of patients suspected of central nervous system lupus. (orig.)

  19. 49 CFR 1542.207 - Access control systems.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Access control systems. 1542.207 Section 1542.207..., DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control systems. (a) Secured area. Except as provided in paragraph (b) of this section, the measures...

  20. Analysis of Access Control Policies in Operating Systems

    Science.gov (United States)

    Chen, Hong

    2009-01-01

    Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the…

  1. Analysis of Access Control Policies in Operating Systems

    Science.gov (United States)

    Chen, Hong

    2009-01-01

    Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the…

  2. OMERACT Rheumatoid Arthritis Magnetic Resonance Imaging Studies. Core set of MRI acquisitions, joint pathology definitions, and the OMERACT RA-MRI scoring system

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Peterfy, C; Conaghan, P

    2003-01-01

    This article describes the 2002 OMERACT rheumatoid arthritis magnetic resonance image scoring system (RAMRIS) for evaluation of inflammatory and destructive changes in RA hands and wrists, which was developed by an international MRI-OMERACT group. MRI definitions of important RA joint pathologies...

  3. Ultrasound-fluoroscopy guided access to the intrarenal excretory system.

    Science.gov (United States)

    Montanari, E; Serrago, M; Esposito, N; Rocco, B; Kartalas-Goumas, I; Del Nero, A; Zanetti, G; Trinchieri, A; Pisani, E

    1999-01-01

    The access to the collecting system can be performed under fluoroscopy computerized tomography, ultrasonographic, mixed ultrasonographic and fluoroscopic guidance. In this paper the creation of a percutaneous transparenchymal ultrasound-fluoroscopy guided access to the intrarenal collecting system completely performed by urologist for different purposes is presented. In five years 297 patients underwent 330 percutaneous kidney accesses to perform derivative nephrostomies (217 pts), percutaneous nephrolithotomies (37 pts), antegrade ureteral manoeuvres (34 pts), antegrade endopyelotomies (7 pts), transitional cell carcinoma of the upper tract resection (2 pts). 11 patients out of these had a percutaneous kidney access in a transplanted kidney. The percutaneous access was successful in 98% of the attemps. A posterior calyx of the lower group (74%), of the medium group (25%) or of the upper group (1%) was accessed. In 73 accesses the mean target calyx diameter was 12.8 mm (range 5-45 mm), the mean operative time 5.4 minutes and the mean fluoroscopy time 5.1 seconds. In 84.5% of the patients the access was performed under local anesthesia when a dilation of the tract was not required. Gross haematuria was observed in 3.9% of the accesses and an arterial lesion treated by embolization in 0.9% of the accesses. Blood transfusion was required in 0.3% of the patients. The ultrasound-fluoroscopy guided access is at least as precise as the fluoroscopy guided one moreover it makes the procedure less invasive and it makes more precise the surgical planning.

  4. Speed control system for an access gate

    Science.gov (United States)

    Bzorgi, Fariborz M.

    2012-03-20

    An access control apparatus for an access gate. The access gate typically has a rotator that is configured to rotate around a rotator axis at a first variable speed in a forward direction. The access control apparatus may include a transmission that typically has an input element that is operatively connected to the rotator. The input element is generally configured to rotate at an input speed that is proportional to the first variable speed. The transmission typically also has an output element that has an output speed that is higher than the input speed. The input element and the output element may rotate around a common transmission axis. A retardation mechanism may be employed. The retardation mechanism is typically configured to rotate around a retardation mechanism axis. Generally the retardation mechanism is operatively connected to the output element of the transmission and is configured to retard motion of the access gate in the forward direction when the first variable speed is above a control-limit speed. In many embodiments the transmission axis and the retardation mechanism axis are substantially co-axial. Some embodiments include a freewheel/catch mechanism that has an input connection that is operatively connected to the rotator. The input connection may be configured to engage an output connection when the rotator is rotated at the first variable speed in a forward direction and configured for substantially unrestricted rotation when the rotator is rotated in a reverse direction opposite the forward direction. The input element of the transmission is typically operatively connected to the output connection of the freewheel/catch mechanism.

  5. WE-EF-BRD-02: Battling Maxwell’s Equations: Physics Challenges and Solutions for Hybrid MRI Systems

    Energy Technology Data Exchange (ETDEWEB)

    Keall, P. [University of Sydney (Australia)

    2015-06-15

    MRI-guided treatment is a growing area of medicine, particularly in radiotherapy and surgery. The exquisite soft tissue anatomic contrast offered by MRI, along with functional imaging, makes the use of MRI during therapeutic procedures very attractive. Challenging the utility of MRI in the therapy room are many issues including the physics of MRI and the impact on the environment and therapeutic instruments, the impact of the room and instruments on the MRI; safety, space, design and cost. In this session, the applications and challenges of MRI-guided treatment will be described. The session format is: Past, present and future: MRI-guided radiotherapy from 2005 to 2025: Jan Lagendijk Battling Maxwell’s equations: Physics challenges and solutions for hybrid MRI systems: Paul Keall I want it now!: Advances in MRI acquisition, reconstruction and the use of priors to enable fast anatomic and physiologic imaging to inform guidance and adaptation decisions: Yanle Hu MR in the OR: The growth and applications of MRI for interventional radiology and surgery: Rebecca Fahrig Learning Objectives: To understand the history and trajectory of MRI-guided radiotherapy To understand the challenges of integrating MR imaging systems with linear accelerators To understand the latest in fast MRI methods to enable the visualisation of anatomy and physiology on radiotherapy treatment timescales To understand the growing role and challenges of MRI for image-guided surgical procedures My disclosures are publicly available and updated at: http://sydney.edu.au/medicine/radiation-physics/about-us/disclosures.php.

  6. Influence of the Application of MRI on the T, N Staging System of Nasopharyngeal Carcinoma

    Institute of Scientific and Technical Information of China (English)

    ChuanmiaoXie; BilingLiang; HaogaoUn; PeihongWu

    2004-01-01

    OBJECTIVE To investigate the influence of utilizing MRI on the T, N staging system (the 5th edition, UICC) and on the 1992 China staging systems (Fuzhou-Guangzhou,China) by comparing the results of CT and MRI examinations of nasopharyngeal carcinoma (NPC).METHODS All 56 NPC patients, which were confirmed by histology,accepted both CT and MRI examinations. CT system scans were obtained by using an Elscient CT Twin Flash with the conventional axial scan. Three cases were examined by an additional coronary scan and 16 patients received an enhanced CT. The MR imaging was performed with a 0.5T MR system (Philips T5- II Ultra-Magnetic). The conventional axial, sagittal and coronary sections with SE sequences were obtained. The scan field was from the supra sellar cistern to the inferior border of C2. Most patients (50/56) accepted contrast enhanced MRI.RESULTS The pharyngobasilar fascia can clearly be seen on MRI but not on CT, so MRI can accurately determine the lesion in the nasopharyngeal cavity. MRI is more sensitive for evaluation of tumor involvement of soft tissue such as the Iongus colli muscle (14 cases by CT and 26 by MRI), tensor veli patalini muscle and levator veli palatini muscle (17 cases by CT and 23 by MRI), and skull-base bone marrow invasion (15 cases by CT and 42 by MRI). MRI can also demonstrate the invasion of the carotid sheath area and the enlargement of retropharyngeal lymph nodes more definitely than CT.The involvement of the trigeminal nerve can be detected on MRI, which may influence the clinical staging directly.CONCLUSION Of the 56 cases examined, 16 (28.6%) changed the staging based on UICC staging; while 33.9% (19/56) cases changed based on the 1992 China-stagin9 system. The major influence of MRI examinations on the 1992 staging was to differentiate the involvement of the carotid sheath area from metastasis of the retropharyngeal lymph nodes. There also was a significant difference in finding early invasion of the skull base.

  7. Parametric analysis of fMRI data using linear systems methods.

    Science.gov (United States)

    Cohen, M S

    1997-08-01

    Using a model of the functional MRI (fMRI) impulse response based on published data, we have demonstrated that the form of the fMRI response to stimuli of freely varied timing can be modeled well by convolution of the impulse response with the behavioral stimulus. The amplitudes of the responses as a function of parametrically varied behavioral conditions are fitted well using a piecewise linear approximation. Use of the combined model, in conjunction with correlation analysis, results in an increase in sensitivity for the MRI study. This approach, based on the well-established methods of linear systems analysis, also allows a quantitative comparison of the response amplitudes across subjects to a broad range of behavioral conditions. Fit parameters, derived from the amplitude data, are relatively insensitive to a variety of MRI-related artifacts and yield results that are compared readily across subjects.

  8. Multi-sensor system for simultaneous ultra-low-field MRI and MEG

    CERN Document Server

    Zotev, V S; Matlachov, A N; Mosher, J C; Newman, S G; Sandin, H J; Urbaitis, A V; Volegov, P L

    2006-01-01

    Magnetoencephalography (MEG) and magnetic resonance imaging at ultra-low fields (ULF MRI) are two methods based on the ability of SQUID (superconducting quantum interference device) sensors to detect femtotesla magnetic fields. Combination of these methods will allow simultaneous functional (MEG) and structural (ULF MRI) imaging of the human brain. In this paper, we report the first implementation of a multi-sensor SQUID system designed for both MEG and ULF MRI. We present a multi-channel image of a human hand obtained at 46 microtesla field, as well as results of auditory MEG measurements with the new system.

  9. Characterization of acoustic noise in a neonatal intensive care unit MRI system

    Energy Technology Data Exchange (ETDEWEB)

    Tkach, Jean A.; Li, Yu; Pratt, Ronald G.; Loew, Wolfgang; Daniels, Barret R.; Giaquinto, Randy O.; Dumoulin, Charles L. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Department of Radiology, Cincinnati, OH (United States); Baroch, Kelly A. [Cincinnati Children' s Hospital Medical Center, Division of Audiology, Cincinnati, OH (United States); Merhar, Stephanie L. [Cincinnati Children' s Hospital Medical Center, Division of Neonatology and Pulmonary Biology, Perinatal Institute, Cincinnati, OH (United States); Kline-Fath, Beth M. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2014-08-15

    To eliminate the medical risks and logistical challenges of transporting infants from the neonatal intensive care unit (NICU) to the radiology department for magnetic resonance imaging, a small-footprint 1.5-T MRI scanner has been developed for neonatal imaging within the NICU. MRI is known to be noisy, and exposure to excessive acoustic noise has the potential to elicit physiological distress and impact development in the term and preterm infant. To measure and compare the acoustic noise properties of the NICU MRI system against those of a conventional 1.5-T MRI system. We performed sound pressure level measurements in the NICU MRI scanner and in a conventional adult-size whole-body 1.5-T MRI system. Sound pressure level measurements were made for six standard clinical MR imaging protocols. The average sound pressure level value, reported in unweighted (dB) and A-weighted (dBA) decibels for all six imaging pulse sequences, was 73.8 dB and 88 dBA for the NICU scanner, and 87 dB and 98.4 dBA for the conventional MRI scanner. The sound pressure level values measured on the NICU scanner for each of the six MR imaging pulse sequences were consistently and significantly (P = 0.03) lower, with an average difference of 14.2 dB (range 10-21 dB) and 11 dBA (range 5-18 dBA). The sound pressure level frequency response of the two MR systems showed a similar harmonic structure above 200 Hz for all imaging sequences. The amplitude, however, was appreciably lower for the NICU scanner, by as much as 30 dB, for frequencies below 200 Hz. The NICU MRI system is quieter than conventional MRI scanners, improving safety for the neonate and facilitating siting of the unit within the NICU. (orig.)

  10. The DAMASK trial protocol: a pragmatic randomised trial to evaluate whether GPs should have direct access to MRI for patients with suspected internal derangement of the knee

    Directory of Open Access Journals (Sweden)

    Orchard Jo

    2006-10-01

    Full Text Available Abstract Background Though new technologies like Magnetic Resonance Imaging (MRI may be accurate, they often diffuse into practice before thorough assessment of their value in diagnosis and management, and of their effects on patient outcome and costs. MRI of the knee is a common investigation despite concern that it is not always appropriate. There is wide variation in general practitioners (GPs access to, and use of MRI, and in the associated costs. The objective of this study was to resolve uncertainty whether GPs should refer patients with suspected internal derangement of the knee for MRI or to an orthopaedic specialist in secondary care. Methods/Design The design consisted of a pragmatic multi-centre randomised trial with two parallel groups and concomitant economic evaluation. Patients presenting in general practice with suspected internal derangement of the knee and for whom their GP was considering referral to an orthopaedic specialist in secondary care were eligible for inclusion. Within practices, GPs or practice nurses randomised eligible and consenting participants to the local radiology department for an MRI examination, or for consultation with an orthopaedic specialist. To ensure that the waiting time from GP consultation to orthopaedic appointment was similar for both trial arms, GPs made a provisional referral to orthopaedics when requesting the MRI examination. Thus we evaluated the more appropriate sequence of events independent of variations in waiting times. Follow up of participants was by postal questionnaires at six, twelve and 24 months after randomisation. This was to ensure that the evaluation covered all events up to and including arthroscopy. Discussion The DAMASK trial should make a major contribution to the development of evidence-based partnerships between primary and secondary care professionals and inform the debate when MRI should enter the diagnostic pathway.

  11. [Mechanical Shimming Method and Implementation for Permanent Magnet of MRI System].

    Science.gov (United States)

    Xue, Tingqiang; Chen, Jinjun

    2015-03-01

    A mechanical shimming method and device for permanent magnet of MRI system has been developed to meet its stringent homogeneity requirement without time-consuming passive shimming on site, installation and adjustment efficiency has been increased.

  12. Testing the quality of images for permanent magnet desktop MRI systems using specially designed phantoms.

    Science.gov (United States)

    Qiu, Jianfeng; Wang, Guozhu; Min, Jiao; Wang, Xiaoyan; Wang, Pengcheng

    2013-12-21

    Our aim was to measure the performance of desktop magnetic resonance imaging (MRI) systems using specially designed phantoms, by testing imaging parameters and analysing the imaging quality. We designed multifunction phantoms with diameters of 18 and 60 mm for desktop MRI scanners in accordance with the American Association of Physicists in Medicine (AAPM) report no. 28. We scanned the phantoms with three permanent magnet 0.5 T desktop MRI systems, measured the MRI image parameters, and analysed imaging quality by comparing the data with the AAPM criteria and Chinese national standards. Image parameters included: resonance frequency, high contrast spatial resolution, low contrast object detectability, slice thickness, geometrical distortion, signal-to-noise ratio (SNR), and image uniformity. The image parameters of three desktop MRI machines could be measured using our specially designed phantoms, and most parameters were in line with MRI quality control criterion, including: resonance frequency, high contrast spatial resolution, low contrast object detectability, slice thickness, geometrical distortion, image uniformity and slice position accuracy. However, SNR was significantly lower than in some references. The imaging test and quality control are necessary for desktop MRI systems, and should be performed with the applicable phantom and corresponding standards.

  13. The neuroscience of investing: fMRI of the reward system.

    Science.gov (United States)

    Peterson, Richard L

    2005-11-15

    Functional magnetic resonance imaging (fMRI) has proven a useful tool for observing neural BOLD signal changes during complex cognitive and emotional tasks. Yet the meaning and applicability of the fMRI data being gathered is still largely unknown. The brain's reward system underlies the fundamental neural processes of goal evaluation, preference formation, positive motivation, and choice behavior. fMRI technology allows researchers to dynamically visualize reward system processes. Experimenters can then correlate reward system BOLD activations with experimental behavior from carefully controlled experiments. In the SPAN lab at Stanford University, directed by Brian Knutson Ph.D., researchers have been using financial tasks during fMRI scanning to correlate emotion, behavior, and cognition with the reward system's fundamental neural activations. One goal of the SPAN lab is the development of predictive models of behavior. In this paper we extrapolate our fMRI results toward understanding and predicting individual behavior in the uncertain and high-risk environment of the financial markets. The financial market price anomalies of "value versus glamour" and "momentum" may be real-world examples of reward system activation biasing collective behavior. On the individual level, the investor's bias of overconfidence may similarly be related to reward system activation. We attempt to understand selected "irrational" investor behaviors and anomalous financial market price patterns through correlations with findings from fMRI research of the reward system.

  14. An improved MRI guided ultrasound system for superficial tumor hyperthermia

    Science.gov (United States)

    Zhu, Mengyuan; Shen, Guofeng; Su, Zhiqiang; Chen, Sheng; Wu, Hao

    2017-03-01

    Among many methods in tumor treatment, ultrasound hyperthermia is characterized by non-invasiveness, and it has been proven very effective for clinical treatment. But the problem of monitoring temperature limits its development. MRI-based temperature mapping techniques are safe compared with invasive methods and have been applied to detect temperature changes for a variety of applications. Among these techniques, the proton resonance frequency (PRF) method is relatively advanced. With a temperature measuring experiment and experiment conducted on tumors inside rabbit legs, the effectiveness of PRF method has been proved. This paper is to introduce an MRI guided ultrasound superficial tumor hyperthermia instrument based on PRF method.

  15. Desmoid fibromatosis: MRI features of response to systemic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sheth, Pooja J.; Subhawong, Ty K. [University of Miami Miller School of Medicine/Jackson Memorial Hospital, Department of Radiology, Miami, FL (United States); Del Moral, Spencer; Wilky, Breelyn A.; Trent, Jonathan C. [University of Miami Miller School of Medicine/Sylvester Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Medicine, Miami, FL (United States); Cohen, Jonathan [Oncology and Radiation Associates, Miami, FL (United States); Rosenberg, Andrew E. [University of Miami Miller School of Medicine, Department of Pathology, Miami, FL (United States); Temple, H.T. [Center for Orthopedic Innovations, Miami, FL (United States)

    2016-10-15

    Imaging criteria for measuring the response of desmoid fibromatosis to systemic therapy are not well established. We evaluated a series of patients with desmoids who underwent systemic therapy to document magnetic resonance imaging (MRI) features associated with a positive clinical response. This Institutional Review Board-approved retrospective study included 23 patients (mean age 40.5) with 29 extra-abdominal tumors. Therapeutic regimens included cytotoxic chemotherapy (n = 19), targeted therapy (n = 3), and nonsteroid anti-inflammatory drugs (NSAIDS; n = 1). Clinical effects were categorized as progressive disease, stable, or partial response. Maximum tumor dimension (D{sub max}), approximate tumor volume (V{sub Tumor}), and quantitative tumor T2 hyperintensity and contrast enhancement (relative to muscle) for pre- and post-treatment MRIs were compared. Three lesions progressed, 5 lesions were stable, whereas 21 showed a clinical response. D{sub max} decreased more in responders (mean -11.0 %) than in stable/progressive lesions (mean -3.6 and 0 % respectively, p = 0.28, ANOVA); by Response Evaluation Criteria in Solid Tumors (RECIST 1.1) 27 out of 29 lesions were ''stable,'' including the 3 progressive lesions. In responders, V{sub Tumor} change averaged -29.4 %, but -19.2 % and +32.5 % in stable and progressive lesions respectively (p = 0.002, ANOVA); by 3D criteria 14 out of 29 lesions showed a partial response. T2 hyperintensity decreased by 50-54 % in partial response/stable disease, but only by 10 % in progressive lesions (p = 0.049, t test). Changes in contrast enhancement ranged from -23 % to 0 %, but were not statistically significant among response groups (p = 0.37). Change in T2 hyperintensity showed a positive correlation with volumetric change (r = 0.40). Decreases in volume and T2 hyperintensity reflect the positive response of desmoid fibromatosis to systemic therapy; RECIST 1.1 criteria are not sensitive to clinically

  16. A networked modular hardware and software system for MRI-guided robotic prostate interventions

    Science.gov (United States)

    Su, Hao; Shang, Weijian; Harrington, Kevin; Camilo, Alex; Cole, Gregory; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare; Fischer, Gregory S.

    2012-02-01

    Magnetic resonance imaging (MRI) provides high resolution multi-parametric imaging, large soft tissue contrast, and interactive image updates making it an ideal modality for diagnosing prostate cancer and guiding surgical tools. Despite a substantial armamentarium of apparatuses and systems has been developed to assist surgical diagnosis and therapy for MRI-guided procedures over last decade, the unified method to develop high fidelity robotic systems in terms of accuracy, dynamic performance, size, robustness and modularity, to work inside close-bore MRI scanner still remains a challenge. In this work, we develop and evaluate an integrated modular hardware and software system to support the surgical workflow of intra-operative MRI, with percutaneous prostate intervention as an illustrative case. Specifically, the distinct apparatuses and methods include: 1) a robot controller system for precision closed loop control of piezoelectric motors, 2) a robot control interface software that connects the 3D Slicer navigation software and the robot controller to exchange robot commands and coordinates using the OpenIGTLink open network communication protocol, and 3) MRI scan plane alignment to the planned path and imaging of the needle as it is inserted into the target location. A preliminary experiment with ex-vivo phantom validates the system workflow, MRI-compatibility and shows that the robotic system has a better than 0.01mm positioning accuracy.

  17. ACCESS: Design and Sub-System Performance

    Science.gov (United States)

    Kaiser, Mary Elizabeth; Morris, Matthew J.; McCandliss, Stephan R.; Rasucher, Bernard J.; Kimble, Randy A.; Kruk, Jeffrey W.; Pelton, Russell; Mott, D. Brent; Wen, Hiting; Foltz, Roger; Quijada, Manuel A.; Gum, Jeffery S.; Gardner, Jonathan P.; Kahle, Duncan M.; Benford, Dominic J.; Woodgate, Bruce E.; Wright, Edward L.; Feldman, Paul D.; Hart, Murdock; Moos, H. Warren; Reiss, Adam G.; Bohlin, Ralph; Deustua, Susana E.; Dixon, W. V.; Sahnow, David J.

    2012-01-01

    Establishing improved spectrophotometric standards is important for a broad range of missions and is relevant to many astrophysical problems. ACCESS, "Absolute Color Calibration Experiment for Standard Stars", is a series of rocket-borne sub-orbital missions and ground-based experiments designed to enable improvements in the precision of the astrophysical flux scale through the transfer of absolute laboratory detector standards from the National Institute of Standards and Technology (NIST) to a network of stellar standards with a calibration accuracy of 1% and a spectral resolving power of 500 across the 0.35 -1.7 micrometer bandpass.

  18. Task Delegation Based Access Control Models for Workflow Systems

    Science.gov (United States)

    Gaaloul, Khaled; Charoy, François

    e-Government organisations are facilitated and conducted using workflow management systems. Role-based access control (RBAC) is recognised as an efficient access control model for large organisations. The application of RBAC in workflow systems cannot, however, grant permissions to users dynamically while business processes are being executed. We currently observe a move away from predefined strict workflow modelling towards approaches supporting flexibility on the organisational level. One specific approach is that of task delegation. Task delegation is a mechanism that supports organisational flexibility, and ensures delegation of authority in access control systems. In this paper, we propose a Task-oriented Access Control (TAC) model based on RBAC to address these requirements. We aim to reason about task from organisational perspectives and resources perspectives to analyse and specify authorisation constraints. Moreover, we present a fine grained access control protocol to support delegation based on the TAC model.

  19. Scheduling Heterogeneous Wireless Systems for Efficient Spectrum Access

    Directory of Open Access Journals (Sweden)

    Liao Shenghui

    2010-01-01

    Full Text Available The spectrum scarcity problem emerged in recent years, due to unbalanced utilization of RF (radio frequency bands in the current state of wireless spectrum allocations. Spectrum access scheduling addresses challenges arising from spectrum sharing by interleaving the channel access among multiple wireless systems in a TDMA fashion. Different from cognitive radio approaches which are opportunistic and noncollaborative in general, spectrum access scheduling proactively structures and interleaves the channel access pattern of heterogeneous wireless systems, using collaborative designs by implementing a crucial architectural component—the base stations on software defined radios (SDRs. We discuss our system design choices for spectrum sharing from multiple perspectives and then present the mechanisms for spectrum sharing and coexistence of GPRS+WiMAX and GPRS+WiFi as use cases, respectively. Simulations were carried out to prove that spectrum access scheduling is an alternative, feasible, and promising approach to the spectrum scarcity problem.

  20. A secure network access system for mobile IPv6

    Science.gov (United States)

    Zhang, Hong; Yuan, Man; He, Rui; Jiang, Luliang; Ma, Jian; Qian, Hualin

    2004-03-01

    With the fast development of Internet and wireless and mobile communication technology, the Mobile Internet Age is upcoming. For those providing Mobile Internet services, especially from the view of ISP (Internet Service Provider), current mobile IP protocol is insufficient. Since the Mobile IPv6 protocol will be popular in near future, how to provide a secure mobile IPv6 service is important. A secure mobile IPv6 network access system is highly needed for mobile IPv6 deployment. Current methods and systems are still inadequate, including EAP, PANA, 802.1X, RADIUS, Diameter, etc. In this paper, we describe main security goals for a secure mobile IPv6 access system, and propose a secure network access system to achieve them. This access system consists of access router, attendant and authentication servers. The access procedure is divided into three phases, which are initial phase, authentication and registration phase and termination phase. This system has many advantages, including layer two independent, flexible and extensible, no need to modify current IPv6 address autoconfiguration protocols, binding update optimization, etc. Finally, the security of the protocol in this system is analyzed and proved with Extended BAN logic method, and a brief introduction of system implementation is given.

  1. In-vivo human brain molecular imaging with a brain-dedicated PET/MRI system.

    Science.gov (United States)

    Cho, Zang Hee; Son, Young Don; Choi, Eun Jung; Kim, Hang Keun; Kim, Jeong Hee; Lee, Sang Yoon; Ogawa, Seiji; Kim, Young Bo

    2013-02-01

    Advances in the new-generation of ultra-high-resolution, brain-dedicated positron emission tomography-magnetic resonance imaging (PET/MRI) systems have begun to provide many interesting insights into the molecular dynamics of the brain. First, the finely delineated structural information from ultra-high-field MRI can help us to identify accurate landmark structures, thereby making it easier to locate PET activation sites that are anatomically well-correlated with metabolic or ligand-specific organs in the neural structures in the brain. This synergistic potential of PET/MRI imaging is discussed in terms of neuroscience and neurological research from both translational and basic research perspectives. Experimental results from the hippocampus, thalamus, and brainstem obtained with (18)F-fluorodeoxyglucose and (11)C-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)benzonitrile are used to demonstrate the potential of this new brain PET/MRI system.

  2. Is your system calibrated? MRI gradient system calibration for pre-clinical, high-resolution imaging.

    Directory of Open Access Journals (Sweden)

    James O'Callaghan

    Full Text Available High-field, pre-clinical MRI systems are widely used to characterise tissue structure and volume in small animals, using high resolution imaging. Both applications rely heavily on the consistent, accurate calibration of imaging gradients, yet such calibrations are typically only performed during maintenance sessions by equipment manufacturers, and potentially with acceptance limits that are inadequate for phenotyping. To overcome this difficulty, we present a protocol for gradient calibration quality assurance testing, based on a 3D-printed, open source, structural phantom that can be customised to the dimensions of individual scanners and RF coils. In trials on a 9.4 T system, the gradient scaling errors were reduced by an order of magnitude, and displacements of greater than 100 µm, caused by gradient non-linearity, were corrected using a post-processing technique. The step-by-step protocol can be integrated into routine pre-clinical MRI quality assurance to measure and correct for these errors. We suggest that this type of quality assurance is essential for robust pre-clinical MRI experiments that rely on accurate imaging gradients, including small animal phenotyping and diffusion MR.

  3. A Nanocomplex System as Targeted Contrast Agent Delivery Vehicle for MRI Dynamic Contrast Enhancement Study

    OpenAIRE

    Korotcov, Alexandru; Shan, Liang; Meng, Huan; Wang, Tongxin; Sridhar, Rajagopalan; Zhao, Yuliang; Liang, Xing-Jie; Wang, Paul C.

    2010-01-01

    We have developed and tested a liposomal nanocomplex system, which contains Gd-DTPA as a payload and transferrin on the surface, as a tumor specific targeting MRI contrast agent for studying prostate cancer tumors in mice. In vivo, the probe significantly enhanced the MRI signal. The image contrast between the peripheral region of the tumor and the non-involved muscle was nearly 50% higher two hours after administration of the nanocomplex. The liposomal nanocomplex increased the amount of Gd ...

  4. CDC STATE System E-Cigarette Legislation - Youth Access

    Data.gov (United States)

    U.S. Department of Health & Human Services — 1995-2016. Centers for Disease Control and Prevention (CDC). State Tobacco Activities Tracking and Evaluation (STATE) System. E-Cigarette Legislation—Youth Access....

  5. Clinical evaluation of shoulder kinematic MRI using an open-type system

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Seiichiro [Okayama Univ. (Japan). Hospital; Togami, Izumi; Sasai, Nobuya [and others

    2000-08-01

    Previous studies on kinematic MRI of the shoulder using cylindrical-type MRI systems were limited to internal or external rotation. The open-type MRI system enables kinematic MRI to be carried out for the abductive position, and is expected to permit evaluation of the superior and inferior glenoid labrum. It is important to evaluate the superior and inferior glenoid labrum in cases of sports injuries (baseball, tennis, etc.). We evaluated the superior and inferior glenoid labrum for abductive motion in asymptomatic healthy volunteers as a preliminary study. As the abduction angle increased, the superior labrum moved into the joint space. Its shape changed from round or triangular to crescent (p<0.0001), and there was increased signal for larger abduction angles (p<0.0001). On the other hand, the shape of the inferior labrum tended to change from crescent to triangular or round (p<0.0001). Increased signal was seen in the inferior labrum on about half the shoulders (N.P.). This did not change as the abduction angle increased. Our results define normal patterns for the superior and inferior glenoid labrum on abductive kinematic MRI in healthy volunteers. Abductive kinematic studies using an open-type MRI system, which permits dynamic evaluation of the superior and inferior glenoid labrum, are expected to be useful for various patients with sports injuries. (author)

  6. Personnel Access Control System Evaluation for National Ignition Facility Operations

    Energy Technology Data Exchange (ETDEWEB)

    Altenbach, T; Brereton, S.; Hermes, G.; Singh, M.

    2001-06-01

    The purpose of this document is to analyze the baseline Access Control System for the National Ignition Facility (NIF), and to assess its effectiveness at controlling access to hazardous locations during full NIF operations. It reviews the various hazards present during a NIF shot sequence, and evaluates the effectiveness of the applicable set of controls at preventing access while the hazards are present. It considers only those hazards that could potentially be lethal. In addition, various types of technologies that might be applicable at NIF are reviewed, as are systems currently in use at other facilities requiring access control for safety reasons. Recommendations on how this system might be modified to reduce risk are made.

  7. The role of diffusion-weighted echo planar MRI in central nervous system infections regarding etiopathogeneses.

    Science.gov (United States)

    Kıroğlu, Yılmaz; Karabulut, Nevzat; Alkan, Alpay

    2010-12-01

    Neuroimaging constitutes an important component in the diagnosis of the underlying infectious agents in central nervous system (CNS) infections. Despite the recent advances in neuroimaging evaluation, the diagnosis of unclear infectious CNS diseases remains a challenge. Conventional magnetic resonance imaging (MRI) is used in routine practice to identify abnormal areas involved in CNS infections. More recent MRI techniques, such as diffusion-weighted imaging (DWI), provide additional helpful information in the assessment of CNS infectious lesions compared with conventional MRI. This pictorial essay summarizes the clinical role of DWI in the demonstration of CNS infections including meningitis, encephalitis and pyogenic infections, and determination of the lesions compared with conventional MRI on the basis of physiopathologic phases of the infections.

  8. Channel Access Algorithm Design for Automatic Identification System

    Institute of Scientific and Technical Information of China (English)

    Oh Sang-heon; Kim Seung-pum; Hwang Dong-hwan; Park Chan-sik; Lee Sang-jeong

    2003-01-01

    The Automatic Identification System (AIS) is a maritime equipment to allow an efficient exchange of the navigational data between ships and between ships and shore stations. It utilizes a channel access algorithm which can quickly resolve conflicts without any intervention from control stations. In this paper, a design of channel access algorithm for the AIS is presented. The input/output relationship of each access algorithm module is defined by drawing the state transition diagram, dataflow diagram and flowchart based on the technical standard, ITU-R M.1371. In order to verify the designed channel access algorithm, the simulator was developed using the C/C++ programming language. The results show that the proposed channel access algorithm can properly allocate transmission slots and meet the operational performance requirements specified by the technical standard.

  9. A mobile console for local access to accelerator control systems.

    CERN Multimedia

    1981-01-01

    Microprocessors were installed as auxiliary crate controllers (ACCs) in the CAMAC interface of control systems for various accelerators. The same ACC was also at the hearth of a stand-alone system in the form of a mobile console. This was also used for local access to the control systems for tests and development work (Annual Report 1981, p. 80, Fig. 10).

  10. A new access control system by fingerprint for radioisotope facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Hiroko; Hirata, Yasuki [Kyushu Univ., Fukuoka (Japan). Radioisotope Center; Kondo, Takahiro; Takatsuki, Katsuhiro

    1998-04-01

    We applied a new fingerprint checker for complete access control to the radiation controlled area and to the radioisotope storage room, and prepared softwares for the best use of this checker. This system consists of a personal computer, access controllers, a fingerprint register, fingerprint checkers, a tenkey and mat sensors, permits ten thousand users to register their fingerprints and its hard disk to keep more than a million records of user`s access. Only 1% of users could not register their fingerprints worn-out, registered four numbers for a fingerprint. The softwares automatically provide varieties of reports, caused a large reduction in manual works. (author)

  11. Efficient medium access control protocol for geostationary satellite systems

    Institute of Scientific and Technical Information of China (English)

    王丽娜; 顾学迈

    2004-01-01

    This paper proposes an efficient medium access control (MAC) protocol based on multifrequency-time division multiple access (MF-TDMA) for geostationary satellite systems deploying multiple spot-beams and onboard processing,which uses a method of random reservation access with movable boundaries to dynamically request the transmission slots and can transmit different types of traffic. The simulation results have shown that our designed MAC protocol can achieve a high bandwidth utilization, while providing the required quality of service (QoS) for each class of service.

  12. ISAIA: Interoperable Systems for Archival Information Access

    Science.gov (United States)

    Hanisch, Robert J.

    2002-01-01

    The ISAIA project was originally proposed in 1999 as a successor to the informal AstroBrowse project. AstroBrowse, which provided a data location service for astronomical archives and catalogs, was a first step toward data system integration and interoperability. The goals of ISAIA were ambitious: '...To develop an interdisciplinary data location and integration service for space science. Building upon existing data services and communications protocols, this service will allow users to transparently query hundreds or thousands of WWW-based resources (catalogs, data, computational resources, bibliographic references, etc.) from a single interface. The service will collect responses from various resources and integrate them in a seamless fashion for display and manipulation by the user.' Funding was approved only for a one-year pilot study, a decision that in retrospect was wise given the rapid changes in information technology in the past few years and the emergence of the Virtual Observatory initiatives in the US and worldwide. Indeed, the ISAIA pilot study was influential in shaping the science goals, system design, metadata standards, and technology choices for the virtual observatory. The ISAIA pilot project also helped to cement working relationships among the NASA data centers, US ground-based observatories, and international data centers. The ISAIA project was formed as a collaborative effort between thirteen institutions that provided data to astronomers, space physicists, and planetary scientists. Among the fruits we ultimately hoped would come from this project would be a central site on the Web that any space scientist could use to efficiently locate existing data relevant to a particular scientific question. Furthermore, we hoped that the needed technology would be general enough to allow smaller, more-focused community within space science could use the same technologies and standards to provide more specialized services. A major challenge to searching

  13. MRI of plants and foods

    Science.gov (United States)

    Van As, Henk; van Duynhoven, John

    2013-04-01

    The importance and prospects for MRI as applied to intact plants and to foods are presented in view of one of humanity's most pressing concerns, the sustainable and healthy feeding of a worldwide increasing population. Intact plants and foods have in common that their functionality is determined by complex multiple length scale architectures. Intact plants have an additional level of complexity since they are living systems which critically depend on transport and signalling processes between and within tissues and organs. The combination of recent cutting-edge technical advances and integration of MRI accessible parameters has the perspective to contribute to breakthroughs in understanding complex regulatory plant performance mechanisms. In food science and technology MRI allows for quantitative multi-length scale structural assessment of food systems, non-invasive monitoring of heat and mass transport during shelf-life and processing, and for a unique view on food properties under shear. These MRI applications are powerful enablers of rationally (re)designed food formulations and processes. Limitations and bottlenecks of the present plant and food MRI methods are mainly related to short T2 values and susceptibility artefacts originating from small air spaces in tissues/materials. We envisage cross-fertilisation of solutions to overcome these hurdles in MRI applications in plants and foods. For both application areas we witness a development where MRI is moving from highly specialised equipment to mobile and downscaled versions to be used by a broad user base in the field, greenhouse, food laboratory or factory.

  14. Flagellated Magnetotactic Bacteria as Controlled MRI-trackable Propulsion and Steering Systems for Medical Nanorobots Operating in the Human Microvasculature.

    Science.gov (United States)

    Martel, Sylvain; Mohammadi, Mahmood; Felfoul, Ouajdi; Lu, Zhao; Pouponneau, Pierre

    2009-04-01

    Although nanorobots may play critical roles for many applications in the human body such as targeting tumoral lesions for therapeutic purposes, miniaturization of the power source with an effective onboard controllable propulsion and steering system have prevented the implementation of such mobile robots. Here, we show that the flagellated nanomotors combined with the nanometer-sized magnetosomes of a single Magnetotactic Bacterium (MTB) can be used as an effective integrated propulsion and steering system for devices such as nanorobots designed for targeting locations only accessible through the smallest capillaries in humans while being visible for tracking and monitoring purposes using modern medical imaging modalities such as Magnetic Resonance Imaging (MRI). Through directional and magnetic field intensities, the displacement speeds, directions, and behaviors of swarms of these bacterial actuators can be controlled from an external computer.

  15. Assessment of Deafblind Access to Manual Language Systems (ADAMLS)

    Science.gov (United States)

    Blaha, Robbie; Carlson, Brad

    2007-01-01

    This document presents the Assessment of Deafblind Access to Manual Language Systems (ADAMLS), a resource for educational teams who are responsible for developing appropriate adaptations and strategies for children who are deafblind who are candidates for learning manual language systems. The assessment tool should be used for all children with a…

  16. Embedded Systems Programming: Accessing Databases from Esterel

    Directory of Open Access Journals (Sweden)

    White David

    2008-01-01

    Full Text Available Abstract A current limitation in embedded controller design and programming is the lack of database support in development tools such as Esterel Studio. This article proposes a way of integrating databases and Esterel by providing two application programming interfaces (APIs which enable the use of relational databases inside Esterel programs. As databases and Esterel programs are often executed on different machines, result sets returned as responses to database queries may be processed either locally and according to Esterel's synchrony hypothesis, or remotely along several of Esterel's execution cycles. These different scenarios are reflected in the design and usage rules of the two APIs presented in this article, which rely on Esterel's facilities for extending the language by external data types, external functions, and procedures, as well as tasks. The APIs' utility is demonstrated by means of a case study modelling an automated warehouse storage system, which is constructed using Lego Mindstorms robotics kits. The robot's controller is programmed in Esterel in a way that takes dynamic ordering information and the warehouse's floor layout into account, both of which are stored in a MySQL database.

  17. Embedded Systems Programming: Accessing Databases from Esterel

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available A current limitation in embedded controller design and programming is the lack of database support in development tools such as Esterel Studio. This article proposes a way of integrating databases and Esterel by providing two application programming interfaces (APIs which enable the use of relational databases inside Esterel programs. As databases and Esterel programs are often executed on different machines, result sets returned as responses to database queries may be processed either locally and according to Esterel’s synchrony hypothesis, or remotely along several of Esterel’s execution cycles. These different scenarios are reflected in the design and usage rules of the two APIs presented in this article, which rely on Esterel’s facilities for extending the language by external data types, external functions, and procedures, as well as tasks. The APIs’ utility is demonstrated by means of a case study modelling an automated warehouse storage system, which is constructed using Lego Mindstorms robotics kits. The robot’s controller is programmed in Esterel in a way that takes dynamic ordering information and the warehouse’s floor layout into account, both of which are stored in a MySQL database.

  18. New MRI grading system for the diagnosis and management of mycetoma.

    Science.gov (United States)

    El Shamy, M E; Fahal, A H; Shakir, M Y; Homeida, M M A

    2012-12-01

    The management of patients with mycetoma depends on accurate identification of the causative organisms and of the extent of disease involvement along the different tissue planes. Disease involvement cannot accurately be assessed with the available diagnostic tools, so in this study we set out to evaluate the effectiveness of MRI in the diagnosis and management of mycetoma. Forty-two patients with confirmed mycetoma had MRI examination of the affected parts. A grading system, The Mycetoma Skin, Muscle, Bone Grading System (MSMBS), was used to describe and grade disease severity on the basis of MRI findings. The logistic regression test was used to correlate the clinical and MRI findings. The study showed that MRI can help in the diagnosis and management of mycetoma patients. The dot-in-circle sign, conglomerated foci with low signal intensity and macro- and micro-abscesses on a background of a hypointense matrix are all diagnostic of mycetoma. In patients with mycetoma, the MSMBS can grade disease severity, compare patients and help to manage them. Further studies are needed to determine to what extent the grading system can be used to determine a patient's prognosis. Copyright © 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  19. MRI zoo

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    The basic idea was to use MRI to produce a sequence of 3D gray scale image slices of various animals, subsequentlyimaged with a clinical CT system. For this purpose, these animals were used: toad, lungfish, python snake and a horseshoe crab. Each animal was sacrificed according to standard....... MRI was done using a Philips Achieva 1.5 T system and CT was performed using a Siemens Somatom system. Axial and sagittal slices were acquired using standard T1w and T2w MRI sequences, and visualization was made using the Mistar software (Apollo Imaging Technology, Melbourne, Australia). Images were...

  20. Abnormal findings of magnetic resonance imaging (MRI) in patients with systemic lupus erythematosus involving the brain

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Akira; Okada, Jun; Kondo, Hirobumi (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine); Kashiwazaki, Sadao

    1992-06-01

    To elucidate the clinical significance of MRI on central nervous system systemic lupus erythematosus (CNS-SLE), MRI and CT scans were performed in 35 patients with SLE, of 18 patients who had CNS manifestations at the time of MRI examinations. The investigations were also carried out in 17 patients without CNS-SLE. The rate of detection of abnormal findings on MRI in patients with CNS-SLE was 77.2% (14/18), which was high, as compared with the rate of those on CT scans (50%: 9/18). Especially, all of 4 patients with seizure and 3 patients with encephalopathy showed abnormal MRI findings, although respectively 50% and 33.3% of them had abnormal CT scan findings. MRI findings were classified into 4 groups below: (1) Large focal are as increased signal intensity at T2 weighted image. These were observed in 2 of 4 patients with seizure and 1 of 3 patients with encephalopathy, which were completely resolved after treatment. (2) Patchy subcortical foci of increased signal intensity at T2 weighted image. These were observed in 11 of 18 CNS-SLE and 7 of 17 without CNS-SLE, which were not detected by CT scan. (3) All of six patients with cerebral infarctions showed high signal intensity areas at T2 weighted image and low signal intensity areas at T1 weighted image. (4) Normal findings were observed in 4 of 18 CNS-SLE (22.2%). We concluded that MRI is useful for the evaluation of CNS-SLE and provides more information than CT scan. (author).

  1. Database design for Physical Access Control System for nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Sathishkumar, T., E-mail: satishkumart@igcar.gov.in; Rao, G. Prabhakara, E-mail: prg@igcar.gov.in; Arumugam, P., E-mail: aarmu@igcar.gov.in

    2016-08-15

    Highlights: • Database design needs to be optimized and highly efficient for real time operation. • It requires a many-to-many mapping between Employee table and Doors table. • This mapping typically contain thousands of records and redundant data. • Proposed novel database design reduces the redundancy and provides abstraction. • This design is incorporated with the access control system developed in-house. - Abstract: A (Radio Frequency IDentification) RFID cum Biometric based two level Access Control System (ACS) was designed and developed for providing access to vital areas of nuclear facilities. The system has got both hardware [Access controller] and software components [server application, the database and the web client software]. The database design proposed, enables grouping of the employees based on the hierarchy of the organization and the grouping of the doors based on Access Zones (AZ). This design also illustrates the mapping between the Employee Groups (EG) and AZ. By following this approach in database design, a higher level view can be presented to the system administrator abstracting the inner details of the individual entities and doors. This paper describes the novel approach carried out in designing the database of the ACS.

  2. HIPPO Experiment Data Access and Subseting System

    Science.gov (United States)

    Krassovski, Misha; Hook, Les; Christensen, Sigurd; Boden, Tom

    2014-05-01

    atmospheric species from nearly pole-to-pole over the Pacific Ocean across all seasons. The suite of atmospheric trace gases and aerosols is pertinent to understanding the carbon cycle and challenging global climate models. This dataset will provide opportunities for research across a broad spectrum of Earth sciences, including those analyzing the evolution in time and space of the greenhouse gases that affect global climate. The Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory (ORNL) provides data management support for the HIPPO experiment including long-term data storage and dissemination. CDIAC has developed a relational database to house HIPPO merged 10-second meteorology, atmospheric chemistry, and aerosol data. This data set provides measurements from all Missions, 1 through 5, that took place from January of 2009 to September 2011. This presentation introduces newly build database and web interface, reflects the present state and functionality of the HIPPO Database and Exploration System as well as future plans for expansion and inclusion of combined discrete flask and GC sample GHG, Halocarbon, and hydrocarbon data.

  3. Access Safety Systems – New Concepts from the LHC Experience

    CERN Document Server

    Ladzinski, T; di Luca, S; Hakulinen, T; Hammouti, L; Riesco, T; Nunes, R; Ninin, P; Juget, J-F; Havart, F; Valentini, F; Sanchez-Corral Mena, E

    2011-01-01

    The LHC Access Safety System has introduced a number of new concepts into the domain of personnel protection at CERN. These can be grouped into several categories: organisational, architectural and concerning the end-user experience. By anchoring the project on the solid foundations of the IEC 61508/61511 methodology, the CERN team and its contractors managed to design, develop, test and commission on time a SIL3 safety system. The system uses a successful combination of the latest Siemens redundant safety programmable logic controllers with a traditional relay logic hardwired loop. The external envelope barriers used in the LHC include personnel and material access devices, which are interlocked door-booths introducing increased automation of individual access control, thus removing the strain from the operators. These devices ensure the inviolability of the controlled zones by users not holding the required credentials. To this end they are equipped with personnel presence detectors and th...

  4. MRI compatible small animal monitoring and trigger system for whole body scanners

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, Karl-Heinz; Krumbein, Ines; Reichenbach, Juergen R. [Jena University Hospital (Germany). Medical Physics Group; Pfeiffer, Norman [Jena University Hospital (Germany). Medical Physics Group; Ernst-Abbe-Fachhochschule Jena (Germany); Herrmann, Lutz [Ernst-Abbe-Fachhochschule Jena (Germany)

    2014-03-01

    Performing magnetic resonance imaging (MRI) experiments with small animals requires continuous monitoring of vital parameters, especially the respiration rate. Clinical whole-body MR scanners represent an attractive option for preclinical imaging as dedicated animal scanners are cost-intensive in both investment and maintenance, thus limiting their availability. Even though impressive image quality is achievable with clinical MR systems in combination with special coils, their built-in physiologic monitoring and triggering units are often not suited for small animal imaging. In this work, we present a simple, MRI compatible low cost solution to monitor the respiration and heart rate of small animals in a clinical whole-body MR scanner. The recording and processing of the biosignals as well as the optimisation of the respiratory trigger generation is described. Additionally rat and mouse in-vivo MRI experiments are presented to illustrate the effectiveness of the monitoring and respiratory trigger system in suppressing motion artifacts. (orig.)

  5. Design considerations and experimental results for MRI systems using HTS magnets

    Science.gov (United States)

    Parkinson, Ben

    2017-01-01

    An increasing number of magnetic resonance imaging (MRI) systems using high temperature superconductors (HTS) magnets have been designed and constructed, with detailed results of their performance now available. Features of REBCO and BSCCO conductors are described as they pertain to use in high homogeneity magnets, with emphasis placed on the practical use of these conductors in magnets. Methods of coil winding are discussed, in particular the differences between pancake and layer winding techniques. Design considerations for HTS magnets are presented in light of the difficulties presented by quench in these magnets, but also in terms of the features of HTS magnets afforded by their high operating temperatures, namely robust cryogen free operation and the potential to use unshielded gradient coils. Drawing on two example MRI systems, namely a 3 T BSCCO brain imaging magnet developed in Japan and a 1.5 T REBCO orthopaedic imaging system developed in New Zealand, the report details real-world stability and homogeneity of HTS-MRI systems, in particular with regards to the screening current effects observed in these systems. It is concluded that, apart from conductor cost, there are currently no technical obstacles to use of HTS-MRI systems.

  6. Development of a flexible optical fiber based high resolution integrated PET∕MRI system.

    Science.gov (United States)

    Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Watabe, Tadashi; Aoki, Masaaki; Sugiyama, Eiji; Kato, Katsuhiko; Hatazawa, Jun

    2012-11-01

    The simultaneous measurement of PET and magnetic resonance imaging (MRI) is an emerging field for molecular imaging research. Although optical fiber based PET∕MRI systems have advantages on less interference between PET and MRI, there is a drawback in reducing the scintillation light due to the fiber. To reduce the problem, the authors newly developed flexible optical fiber bundle based block detectors and employed them for a high resolution integrated PET∕MRI system. The flexible optical fiber bundle used 0.5 mm diameter, 80 cm long double clad fibers which have dual 12 mm × 24 mm rectangular inputs and a single 24 mm × 24 mm rectangular output. In the input surface, LGSO scintillators of 0.025 mol.% (decay time: ∼31 ns: 0.9 mm × 1.3 mm × 5 mm) and 0.75 mol.% (decay time: ∼46 ns: 0.9 mm × 1.3 mm × 6 mm) were optically coupled in depth direction to form depth-of-interaction detector, arranged in 11 × 13 matrix and optically coupled to the fiber bundle. The two inputs of the bundle are bent for 90°, bound to one, and are optically coupled to a Hamamatsu 1-in. square position sensitive photomultiplier tube. Light loss due to the fiber bundle could be reduced and the performance of the block detectors was improved. Eight optical fiber based block detectors (16 LGSO blocks) were arranged in a 56 mm diameter ring to form a PET system. Spatial resolution and sensitivity were 1.2 mm full-width at half-maximum and 1.2% at the central field-of-view, respectively. Sensitivity change was less than 1% for 2 °C temperature changes. This PET system was integrated with a 0.3 T permanent magnet MRI system which has 17 cm diameter hole at the yoke area for insertion of the PET detector ring. There was no observable interference between PET and MRI. Simultaneous imaging of PET and MRI was successfully performed for small animal studies. The authors confirmed that the developed high resolution PET∕MRI system is promising for molecular

  7. A system for MRI-guided transperineal delivery of needles to the prostate for focal therapy.

    Science.gov (United States)

    Cepek, Jeremy; Chronik, Blaine A; Lindner, Uri; Trachtenberg, John; Davidson, Sean R H; Bax, Jeffrey; Fenster, Aaron

    2013-01-01

    To demonstrate the capabilities of a new magnetic resonance imaging (MRI)-guided system for delivering needles to the prostate for focal therapy. Included is a presentation of the design of the system and its user interface, evaluation of MR-compatibility, and quantitative evaluation of guidance accuracy and repeatability within the bore of a clinical MRI scanner. The use of MRI for visualization of tumors, intraoperative visualization of interventional tools, and thermometry for controlled ablation of lesions is becoming increasingly prevalent. In this work, the authors present a prototype system for guiding needles to prostate tumors within the bore of an MRI scanner for use in focal laser thermal ablation of prostate tumors. The system consists of a manually actuated trajectory alignment device that allows a physician to precisely align a set of needle guides with an intended target in the prostate within the bore of a clinical closed-bore MRI scanner. Needle insertion is then performed transperineally, with the patient in the bore of the MRI, and custom software provides monitoring of thermal ablative procedures. The system is shown to have a minimal effect on image distortion, and only a 6% decrease in image signal-to-noise ratio. Through needle insertion tests in tissue-mimicking phantoms, the system's potential for reliably guiding needles to intra-MR targets within 2.64 mm has been demonstrated. Use of the system to deliver focal laser ablation therapy to two patients showed that it can be used to deliver needles with minimal disruption of workflow, and in less time than when insertions are performed freehand or with a fixed grid template. A system for delivering needles to a patient's prostate for focal therapy within the bore of an MRI scanner has been developed. Results from needle insertion tests in phantoms suggest that the system has the potential to provide accurate delivery of focal therapy to prostate tumors of the smallest clinically significant

  8. Accessing and Sharing Data Using the CUAHSI Hydrologic Information System

    Science.gov (United States)

    Tarboton, D. G.; Horsburgh, J. S.; Whiteaker, T. L.; Maidment, D. R.; Zaslavsky, I.

    2008-12-01

    The Consortium of Universities for the Advancement of Hydrologic Science, Inc (CUAHSI) has a Hydrologic Information System (HIS) project, which is developing infrastructure to support the sharing of hydrologic data through web services and tools for data discovery, access and publication. Centralized data services support access to National Datasets such as the USGS National Water Information System (NWIS) and SNOTEL, in a standard way. Distributed data services allow users to establish their own server and publish their data through CUAHSI HIS web services. Once such a data service is registered within HIS Central, it becomes searchable and accessible through the centralized discovery and data access tools. The HIS is founded upon an information model for observations at stationary points that supports its data services. This is implemented as both XML and relational database schema for transmission and storage of data respectively. WaterML is the XML based data transmission model that underlies the machine to machine communications, while the Observations Data Model (ODM) is a relational database model for persistent data storage. Web services support access to hydrologic data stored in ODM and transmitted using WaterML directly from applications software such as Excel, MATLAB and ArcGIS that have Simple Object Access Protocol (SOAP) capability. A significant value of web services derives from the capability to use them from within a user's preferred analysis environment, rather than requiring a user to learn new software. This allows a user to work with data from national and academic sources, almost as though it was on their local disk. This poster will be computer-based with internet access for demonstration of HIS tools and functionality.

  9. Value of MRI of the brain in patients with systemic lupus erythematosus and neurologic disturbance

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, J.E.; Sundgren, P.C.; Maly, P. [Division of Neuroradiology, Department of Radiology, University of Michigan, 1500 East Medical Center Drive, MI 48109, Ann Arbor (United States); Attwood, J.; McCune, J. [Department of Internal Medicine, University of Michigan, 1500 East Medical Center Drive, MI 48109, Ann Arbor (United States)

    2004-01-01

    Our objective was to review the frequency and pattern of signal abnormalities seen on conventional MRI in patients with suspected neuropsychiatric systemic lupus erythematosus (NP-SLE). We reviewed 116 MRI examinations of the brain performed on 85 patients with SLE, (81 women, four men, aged 21-78 years, mean 40.6 years) presenting with neurological disturbances. MRI was normal or nearly normal in 34%. In 60% high-signal lesions were observed on T2-weighted images, frequently in the frontal and parietal subcortical white matter. Infarct-like lesions involving gray and white matter were demonstrated in 21 of cases. Areas of restricted diffusion were seen in 12 of the 67 patients who underwent diffusion-weighted imaging. Other abnormalities included loss of brain volume, hemorrhage, meningeal enhancement, and bilateral high signal in occipital white-matter. The MRI findings alone did not allow us to distinguish between thromboembolic and inflammatory events in many patients. Some patients with normal MRI improved clinically while on immunosuppressive therapy. More sensitive and/or specific imaging methods, such as spectroscopy and perfusion-weighted imaging, should be investigated in these subgroups of patients with suspected NP-SLE. (orig.)

  10. A novel IPTV program multiplex access system to EPON

    Science.gov (United States)

    Xu, Xian; Liu, Deming; He, Wei; Lu, Xi

    2007-11-01

    With the rapid development of high speed networks, such as Ethernet Passive Optical Network (EPON), traffic patterns in access networks have evolved from traditional text-oriented service to the mixed text-, voice- and video- based services, leading to so called "Triple Play". For supporting IPTV service in EPON access network infrastructure, in this article we propose a novel IPTV program multiplex access system to EPON, which enables multiple IPTV program source servers to seamlessly access to IPTV service access port of optical line terminal (OLT) in EPON. There are two multiplex schemes, namely static multiplex scheme and dynamic multiplex scheme, in implementing the program multiplexing. Static multiplex scheme is to multiplex all the IPTV programs and forward them to the OLT, regardless of the need of end-users. While dynamic multiplex scheme can dynamically multiplex and forward IPTV programs according to what the end-users actually demand and those watched by no end-user would not be multiplexed. By comparing these two schemes, a reduced traffic of EPON can be achieved by using dynamic multiplex scheme, especially when most end-users are watching the same few IPTV programs. Both schemes are implemented in our system, with their hardware and software designs described.

  11. Development of a high-resolution detection module for the INSERT SPECT/MRI system

    Energy Technology Data Exchange (ETDEWEB)

    Busca, Paolo; Fiorini, Carlo; Butt, Arslan D; Occhipinti, Michele; Quaglia, Riccardo; Trigilio, Paolo [Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, Via Golgi 40, 20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, 20133 Milano (Italy); Nemeth, Gabor; Major, Peter; Bukki, Tamas; Nagy, Kalman [Mediso Medical Imaging Systems, Alsotorokvesz 14, H-1022 Budapest (Hungary); Piemonte, Claudio; Ferri, Alessandro; Gola, Alberto [Fondazione Bruno Kessler (FBK), Via Sommarive, 18, 38123 Trento (Italy); Rieger, Jan [MRI.TOOLS GmbH, Robert-Roessle-Str. 10, 13125 Berlin (Germany); Niendorf, Thoralf [MRI.TOOLS GmbH, Robert-Roessle-Str. 10, 13125 Berlin (Germany); Berlin Ultrahigh Field Facility (B.UniversityF.F.), Max-Delbrueck-Center for Molecular Medicine, Berlin (Germany)

    2014-07-29

    A new multi-modality imaging tool is under development in the framework of the INSERT (Integrated SPECT/MRI for Enhanced Stratification in Radio-chemo Therapy) project, supported by the European Community. The final goal is to develop a custom SPECT apparatus that can be used as an insert for commercially available MRI systems. INSERT is expected to offer more effective and earlier diagnosis with potentially better outcome in survival for the treatment of brain tumors, primarily glioma. Two SPECT prototypes are being developed, one dedicated to preclinical imaging (7 and 9.4 T), the second one dedicated to clinical imaging (3 T).

  12. Access and Use of Federal Data through NSF's CASPAR System.

    Science.gov (United States)

    Firnberg, James W.

    1991-01-01

    The National Science Foundation's Computer-Aided Science Policy and Research database system provides microcomputer-based access and manipulation of multiple national databases for federal and now institutional use. Applications at West Virginia University, Portland State University, and the State University of New York at Buffalo pilot tested the…

  13. system hardening architecture for safer access to critical business ...

    African Journals Online (AJOL)

    eobe

    a computer system or to inject malicious code into it, aimed at causing harm to ... 34 No. 4, October 2015 789 safer access to stored data, and therefore, decrease in ..... Computer and Communication Engineering, Vol. 3,. Number 1, 2014, pp ...

  14. 45 CFR 95.615 - Access to systems and records.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Access to systems and records. 95.615 Section 95.615 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION GENERAL ADMINISTRATION-GRANT PROGRAMS (PUBLIC ASSISTANCE, MEDICAL ASSISTANCE AND STATE CHILDREN'S HEALTH INSURANCE...

  15. Performance evaluation by means of quality control of MRI system and comparison of institutions

    Energy Technology Data Exchange (ETDEWEB)

    Ogura, Akio [Kyoto City Hospital (Japan); Higashida, Mitsuji; Yamazaki, Masaru; Inoue, Hiroshi; Ishiguro, Akihiro

    2000-06-01

    To evaluate the performance of clinical magnetic resonance imaging systems, standard test procedures have been recommended by the NEMA, AAPM task group, EEC concerted research project, and others. The purpose of these standard tests is to determine system performance specifications, reference procedures for test acceptance, and periodic examination of quality control. However, the recommended measurements are very complicated when used for periodic quality control checks or comparisons with other systems. Therefore, we determined new standard test procedures that serve these purposes. Eleven clinical MRI systems in nine clinical facilities were evaluated using these new standard test sets. Results indicated that the measurement time was too short using the new test sets. However, through comparison with various MRI systems, the specificity of each system could be determined. (author)

  16. Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kennth Marken

    2006-08-11

    The original goal of this Phase II Superconductivity Partnership Initiative project was to build and operate a prototype Magnetic Resonance Imaging (MRI) system using high temperature superconductor (HTS) coils wound from continuously processed dip-coated BSCCO 2212 tape conductor. Using dip-coated tape, the plan was for MRI magnet coils to be wound to fit an established commercial open geometry, 0.2 Tesla permanent magnet system. New electronics and imaging software for a prototype higher field superconducting system would have added significantly to the cost. However, the use of the 0.2 T platform would allow the technical feasibility and the cost issues for HTS systems to be fully established. Also it would establish the energy efficiency and savings of HTS open MRI compared with resistive and permanent magnet systems. The commercial goal was an open geometry HTS MRI running at 0.5 T and 20 K. This low field open magnet was using resistive normal metal conductor and its heat loss was rather high around 15 kolwatts. It was expected that an HTS magnet would dissipate around 1 watt, significantly reduce power consumption. The SPI team assembled to achieve this goal was led by Oxford Instruments, Superconducting Technology (OST), who developed the method of producing commercial dip coated tape. Superconductive Components Inc. (SCI), a leading US supplier of HTS powders, supported the conductor optimization through powder optimization, scaling, and cost reduction. Oxford Magnet Technology (OMT), a joint venture between Oxford Instruments and Siemens and the world’s leading supplier of MRI magnet systems, was involved to design and build the HTS MRI magnet and cryogenics. Siemens Magnetic Resonance Division, a leading developer and supplier of complete MRI imaging systems, was expected to integrate the final system and perform imaging trials. The original MRI demonstration project was ended in July 2004 by mutual consent of Oxford Instruments and Siemens. Between

  17. Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kennth Marken

    2006-08-11

    The original goal of this Phase II Superconductivity Partnership Initiative project was to build and operate a prototype Magnetic Resonance Imaging (MRI) system using high temperature superconductor (HTS) coils wound from continuously processed dip-coated BSCCO 2212 tape conductor. Using dip-coated tape, the plan was for MRI magnet coils to be wound to fit an established commercial open geometry, 0.2 Tesla permanent magnet system. New electronics and imaging software for a prototype higher field superconducting system would have added significantly to the cost. However, the use of the 0.2 T platform would allow the technical feasibility and the cost issues for HTS systems to be fully established. Also it would establish the energy efficiency and savings of HTS open MRI compared with resistive and permanent magnet systems. The commercial goal was an open geometry HTS MRI running at 0.5 T and 20 K. This low field open magnet was using resistive normal metal conductor and its heat loss was rather high around 15 kolwatts. It was expected that an HTS magnet would dissipate around 1 watt, significantly reduce power consumption. The SPI team assembled to achieve this goal was led by Oxford Instruments, Superconducting Technology (OST), who developed the method of producing commercial dip coated tape. Superconductive Components Inc. (SCI), a leading US supplier of HTS powders, supported the conductor optimization through powder optimization, scaling, and cost reduction. Oxford Magnet Technology (OMT), a joint venture between Oxford Instruments and Siemens and the world’s leading supplier of MRI magnet systems, was involved to design and build the HTS MRI magnet and cryogenics. Siemens Magnetic Resonance Division, a leading developer and supplier of complete MRI imaging systems, was expected to integrate the final system and perform imaging trials. The original MRI demonstration project was ended in July 2004 by mutual consent of Oxford Instruments and Siemens. Between

  18. Open access pricing methodology in economically adapted electric transmission systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudnick, Hugh; Cura, Eliana; Palma, Rodrigo [Pontificia Univ. Catolica de Chile, Santiago (Chile). Dept. de Ingenieria Electrica

    1996-07-01

    Open access pricing methodologies are evaluated in a deregulated environment, as applied to an economically adapted electric transmission system over a ten year time horizon. A transmission planning methodology using a genetic algorithm is used to determine the adapted system and the required investment over the horizon. A production cost simulation algorithm is utilized to determine the operation of the hydroelectric system and the resultant short term marginal income. Different pricing methodologies to allocate the required supplement, as applied to the Chilean central interconnected electrical system, are evaluated: use of system, postage stamp and user benefit. The resultant payment allocations are assessed and their economic impact on participants is discussed. (author)

  19. Accessibility of spoken, written, and sign language in Landau-Kleffner syndrome: a linguistic and functional MRI study.

    Science.gov (United States)

    Sieratzki, J S; Calvert, G A; Brammer, M; David, A; Woll, B

    2001-06-01

    Landau-Kleffner syndrome (LKS) is an acquired aphasia which begins in childhood and is thought to arise from an epileptic disorder within the auditory speech cortex. Although the epilepsy usually subsides at puberty, a severe communication impairment often persists. Here we report on a detailed study of a 26-year old, left-handed male, with onset of LKS at age 5 years, who is aphasic for English but who learned British Sign Language (BSL) at age 13. We have investigated his skills in different language modalities, recorded EEGs during wakefulness, sleep, and under conditions of auditory stimulation, measured brain stem auditory-evoked potentials (BAEP), and performed functional MRI (fMRI) during a range of linguistic tasks. Our investigation demonstrated severe restrictions in comprehension and production of spoken English as well as lip-reading, while reading was comparatively less impaired. BSL was by far the most efficient mode of communication. All EEG recordings were normal, while BAEP showed minor abnormalities. fMRI revealed: 1) powerful and extensive bilateral (R > L) activation of auditory cortices in response to heard speech, much stronger than when listening to music; 2) very little response to silent lip-reading; 3) strong activation in the temporo-parieto-occipital association cortex, exclusively in the right hemisphere (RH), when viewing BSL signs. Analysis of these findings provides novel insights into the disturbance of the auditory speech cortex which underlies LKS and its diagnostic evaluation by fMRI, and underpins a strategy of restoring communication abilities in LKS through a natural sign language of the deaf (with Video)

  20. Does the public deserve free access to climate system science?

    Science.gov (United States)

    Grigorov, Ivo

    2010-05-01

    Some time ago it was the lack of public access to medical research data that really stirred the issue and gave inertia for legislation and a new publishing model that puts tax payer-funded medical research in the hands of those who fund it. In today's age global climate change has become the biggest socio-economic challenge, and the same argument resonates: climate affects us all and the publicly-funded science quantifying it should be freely accessible to all stakeholders beyond academic research. Over the last few years the ‘Open Access' movement to remove as much as possible subscription, and other on-campus barriers to academic research has rapidly gathered pace, but despite significant progress, the climate system sciences are not among the leaders in providing full access to their publications and data. Beyond the ethical argument, there are proven and tangible benefits for the next generation of climate researchers to adapt the way their output is published. Through the means provided by ‘open access', both data and ideas can gain more visibility, use and citations for the authors, but also result in a more rapid exchange of knowledge and ideas, and ultimately progress towards a sought solution. The presentation will aim to stimulate discussion and seek progress on the following questions: Should free access to climate research (& data) be mandatory? What are the career benefits of using ‘open access' for young scientists? What means and methods should, or could, be incorporated into current European graduate training programmes in climate research, and possible ways forward?

  1. NASA access mechanism: Graphical user interface information retrieval system

    Science.gov (United States)

    Hunter, Judy; Generous, Curtis; Duncan, Denise

    1993-01-01

    Access to online information sources of aerospace, scientific, and engineering data, a mission focus for NASA's Scientific and Technical Information Program, has always been limited to factors such as telecommunications, query language syntax, lack of standardization in the information, and the lack of adequate tools to assist in searching. Today, the NASA STI Program's NASA Access Mechanism (NAM) prototype offers a solution to these problems by providing the user with a set of tools that provide a graphical interface to remote, heterogeneous, and distributed information in a manner adaptable to both casual and expert users. Additionally, the NAM provides access to many Internet-based services such as Electronic Mail, the Wide Area Information Servers system, Peer Locating tools, and electronic bulletin boards.

  2. NASA Access Mechanism - Graphical user interface information retrieval system

    Science.gov (United States)

    Hunter, Judy F.; Generous, Curtis; Duncan, Denise

    1993-01-01

    Access to online information sources of aerospace, scientific, and engineering data, a mission focus for NASA's Scientific and Technical Information Program, has always been limited by factors such as telecommunications, query language syntax, lack of standardization in the information, and the lack of adequate tools to assist in searching. Today, the NASA STI Program's NASA Access Mechanism (NAM) prototype offers a solution to these problems by providing the user with a set of tools that provide a graphical interface to remote, heterogeneous, and distributed information in a manner adaptable to both casual and expert users. Additionally, the NAM provides access to many Internet-based services such as Electronic Mail, the Wide Area Information Servers system, Peer Locating tools, and electronic bulletin boards.

  3. Portable MRI

    Energy Technology Data Exchange (ETDEWEB)

    Espy, Michelle A. [Los Alamos National Laboratory

    2012-06-29

    This project proposes to: (1) provide the power of MRI to situations where it presently isn't available; (2) perform the engineering required to move from lab to a functional prototype; and (3) leverage significant existing infrastructure and capability in ultra-low field MRI. The reasons for doing this: (1) MRI is the most powerful tool for imaging soft-tissue (e.g. brain); (2) Billions don't have access due to cost or safety issues; (3) metal will heat/move in high magnetic fields; (4) Millions of cases of traumatic brain injury in US alone; (5) even more of non-traumatic brain injury; (6) (e.g. stroke, infection, chemical exposure); (7) Need for early diagnostic; (8) 'Signature' wound of recent conflicts; (9) 22% of injuries; (10) Implications for post-traumatic stress disorder; and (11) chronic traumatic encephalopathy.

  4. Guarantee of property right in opean access systems; Open access ni okeru zaisanken no hosho

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, M. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1996-12-25

    This paper describes discussions in California of the USA and in Germany concerning the separation of transmission department and forced liberation of transmission network in private electric power companies and the guarantee of property right. In California, the state public utility committee does not have an authority to order the separation of transmission department against electric power companies. It is only the legislature that can conduct the separation of transmission department and the third party access of transmission network based on the expropriation provisions of the constitution. In Germany, the order of separation of transmission department by the readjusting authority contradicts the guarantee of property right in the constitution. The order of third party access also exceeds the range of duty accompanied with the property right, and the procedure of expropriation is necessary for its enforcement. Problems are pointed out in the case when these discussions are applied to the separation of transmission department, third party access, and distribution system in Japan. 3 refs.

  5. Personal Access Satellite System (PASS) study. Fiscal year 1989 results

    Science.gov (United States)

    Sue, Miles K. (Editor)

    1990-01-01

    The Jet Propulsion Laboratory is exploring the potential and feasibility of a personal access satellite system (PASS) that will offer the user greater freedom and mobility than existing or currently planned communications systems. Studies performed in prior years resulted in a strawman design and the identification of technologies that are critical to the successful implementation of PASS. The study efforts in FY-89 were directed towards alternative design options with the objective of either improving the system performance or alleviating the constraints on the user terminal. The various design options and system issues studied this year and the results of the study are presented.

  6. Repeated dexamphetamine treatment alters the dopaminergic system and increases the phMRI response to methylphenidate

    Science.gov (United States)

    Schrantee, Anouk; Tremoleda, Jordi L.; Wylezinska-Arridge, Marzena; Bouet, Valentine; Hesseling, Peter; Meerhoff, Gideon F.; de Bruin, Kora M.; Koeleman, Jan; Freret, Thomas; Boulouard, Michel; Desfosses, Emilie; Galineau, Laurent; Gozzi, Alessandro; Dauphin, François; Gsell, Willy; Booij, Jan; Lucassen, Paul J.; Reneman, Liesbeth

    2017-01-01

    Dexamphetamine (AMPH) is a psychostimulant drug that is used both recreationally and as medication for attention deficit hyperactivity disorder. Preclinical studies have demonstrated that repeated exposure to AMPH can induce damage to nerve terminals of dopamine (DA) neurons. We here assessed the underlying neurobiological changes in the DA system following repeated AMPH exposure and pre-treated rats with AMPH or saline (4 times 5 mg/kg s.c., 2 hours apart), followed by a 1-week washout period. We then used pharmacological MRI (phMRI) with a methylphenidate (MPH) challenge, as a sensitive and non-invasive in-vivo measure of DAergic function. We subsequently validated the DA-ergic changes post-mortem, using a.o. high-performance liquid chromatography (HPLC) and autoradiography. In the AMPH pre-treated group, we observed a significantly larger BOLD response to the MPH challenge, particularly in DA-ergic brain areas and their downstream projections. Subsequent autoradiography studies showed that AMPH pre-treatment significantly reduced DA transporter (DAT) density in the caudate-putamen (CPu) and nucleus accumbens, whereas HPLC analysis revealed increases in the DA metabolite homovanillic acid in the CPu. Our results suggest that AMPH pre-treatment alters DAergic responsivity, a change that can be detected with phMRI in rats. These phMRI changes likely reflect increased DA release together with reduced DAT binding. The ability to assess subtle synaptic changes using phMRI is promising for both preclinical studies of drug discovery, and for clinical studies where phMRI can be a useful tool to non-invasively investigate DA abnormalities, e.g. in neuropsychiatric disorders. PMID:28241065

  7. Use of system approaches for transmission open access pricing

    Energy Technology Data Exchange (ETDEWEB)

    Rudnick, H.; Soto, M.; Palma, R. [Pontificia University Catolica de Chile, Santiago (Chile)

    1999-02-01

    The Latin American deregulated markets have based their open access schemes on a concept that considers a multilateral use of the transmission system, with all agents contributing to the financing of a common network based on physical and economic usage, irrespective of commercial arrangements. The paper describes the concept and the existing schemes and contributes with the formulation of alternative numerical approaches for open access pricing, taking into account energy and capacity use of the system by the participant agents. Distribution factors based on DC power flows are the basic elements of the formulation, which is built based on different physical and economic considerations. The approaches are numerically evaluated in the Chilean main interconnected electrical system, with a comparison of the resultant impacts on generators and consumers. (author)

  8. volBrain: an online MRI brain volumetry system

    Directory of Open Access Journals (Sweden)

    Jose V. Manjon

    2016-07-01

    Full Text Available The amount of medical image data produced in clinical and research settings is rapidly growing resulting in vast amount of data to analyze. Automatic and reliable quantitative analysis tools, including segmentation, allow to analyze brain development and to understand specific patterns of many neurological diseases. This field has recently experienced many advances with successful techniques based on non-linear warping and label fusion. In this work we present a novel and fully automatic pipeline for volumetric brain analysis based on multi-atlas label fusion technology that is able to provide accurate volumetric information at different levels of detail in a short time. This method is available through the volBrain online web interface (http://volbrain.upv.es, which is publically and freely accessible to the scientific community. Our new framework has been compared with current state-of-the-art methods showing very competitive results.

  9. Visualization of suspicious lesions in breast MRI based on intelligent neural systems

    Science.gov (United States)

    Twellmann, Thorsten; Lange, Oliver; Nattkemper, Tim Wilhelm; Meyer-Bäse, Anke

    2006-05-01

    Intelligent medical systems based on supervised and unsupervised artificial neural networks are applied to the automatic visualization and classification of suspicious lesions in breast MRI. These systems represent an important component of future sophisticated computer-aided diagnosis systems and enable the extraction of spatial and temporal features of dynamic MRI data stemming from patients with confirmed lesion diagnosis. By taking into account the heterogenity of the cancerous tissue, these techniques reveal the malignant, benign and normal kinetic signals and and provide a regional subclassification of pathological breast tissue. Intelligent medical systems are expected to have substantial implications in healthcare politics by contributing to the diagnosis of indeterminate breast lesions by non-invasive imaging.

  10. Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy.

    Science.gov (United States)

    Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M; Hata, Nobuhiko; Fischer, Gregory S

    2015-08-01

    This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian motion module. The needle driver provides needle cannula translation and rotation (2-DOF) and stylet translation (1-DOF). A custom robot controller consisting of multiple piezoelectric motor drivers provides precision closed-loop control of piezoelectric motors and enables simultaneous robot motion and MR imaging. The developed modular robot control interface software performs image-based registration, kinematics calculation, and exchanges robot commands and coordinates between the navigation software and the robot controller with a new implementation of the open network communication protocol OpenIGTLink. Comprehensive compatibility of the robot is evaluated inside a 3-Tesla MRI scanner using standard imaging sequences and the signal-to-noise ratio (SNR) loss is limited to 15%. The image deterioration due to the present and motion of robot demonstrates unobservable image interference. Twenty-five targeted needle placements inside gelatin phantoms utilizing an 18-gauge ceramic needle demonstrated 0.87 mm root mean square (RMS) error in 3D Euclidean distance based on MRI volume segmentation of the image-guided robotic needle placement procedure.

  11. CT and MRI findings of cerebral ischemic lesions in the cortical and perforating arterial system

    Energy Technology Data Exchange (ETDEWEB)

    Kameyama, Masakuni; Udaka, Fukashi; Nishinaka, Kazuto; Kodama, Mitsuo; Urushidani, Makoto; Kawamura, Kazuyuki; Inoue, Haruhisa; Kageyama, Taku [Sumitomo Hospital, Osaka (Japan)

    1995-07-01

    It is clinically useful to divide the location of infarction into the cortical and perforating arterial system. Computerized tomography (CT) and magnetic resonance imaging (MRI) now make the point of infarction a simple and useful task in daily practice. The diagnostic modality has also demonstrated that risk factors and clinical manifestations are different for infarction in the cortical as opposed to the perforating system. In this paper, we present various aspects of images of cerebral ischemia according to CT and/or MRI findings. With the advance of imaging mechanics, diagnostic capability of CT or/and MRI for cerebral infarction has markedly been improved. We must consider these points on evaluating the previously reported results. In addition, we always consider the pathological background of these image-findings for the precise interpretation of their clinical significance. In some instances, dynamic study such as PET or SPECT is needed for real interpretations of CT and/or MRI images. We paid special reference to lacunar stroke and striatocapsular infarct. In addition, `branch atheromatous disease (Caplan)` was considered, in particular, for their specific clinical significances. Large striatocapsular infarcts frequently show cortical signs and symptoms such as aphasia or agnosia in spite of their subcortical localization. These facts, although have previously been known, should be re-considered for their pathoanatomical mechanism. (author).

  12. Occupational exposure levels of static magnetic field during routine MRI examination in 3T MR system.

    Science.gov (United States)

    Yamaguchi-Sekino, Sachiko; Nakai, Toshiharu; Imai, Shinya; Izawa, Shuhei; Okuno, Tsutomu

    2014-01-01

    Occupational exposure to the high static magnetic fields (SMFs) during magnetic resonance imaging (MRI) examinations raises concerns of adverse health effects. In this study, personal exposure monitoring of the magnetic fields during routine examinations in two 3 T MRI systems was carried out. A three-axis Hall magnetometer was attached to a subject's chest during monitoring. Data acquisition started every time the subject entered the scanner room and ended when the subject exited the room. Four radiologic technologists from two different institutes participated in this study. The maximum exposed field ranged from 0 to 1250 mT and the average peak magnetic field (B) was 428 ± 231 mT (mean ± standard deviation (SD): number of samples (N) = 103). Then, the relationship between exposure levels and work duties was analyzed. The MRI examination of the head or neck showed the highest average peak B among four work categories. These results provide information of real exposure levels for 3 T MRI system operators and can also improve the current practical training advice for preventing extra occupational field exposure.

  13. Visual MRI grading system to evaluate atrophy of the supeaspinatus muscle

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Hyun Kyoung; Hong, Sung Hwan; Yoo, Hye Jin; Choi, Ja Young; Kim, Sae Hoon; Choi, Jung Ah; Kang, Heung Sik [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2014-08-15

    To investigate the interobserver reproducibility and diagnostic feasibility of a visual grading system for assessing atrophy of the supraspinatus muscle on magnetic resonance imaging (MRI). Three independent radiologists retrospectively evaluated the occupying ratio of the supraspinatus muscle in the supraspinatus fossa on 192 shoulder MRI examinations in 188 patients using a 3-point visual grading system (1, ≥ 60%; 2, 30-59%; 3, < 30%) on oblique sagittal T1-weighted images. The inter-reader agreement and the agreement with the reference standard (3-point grades according to absolute occupying ratio values quantitatively measured by directly contouring the muscles on MRI) were analyzed using weighted kappa. The visual grading was applied by a single reader to a group of 100 consecutive patients who had undergone rotator cuff repair to retrospectively determine the association between the visual grades at preoperative state and postsurgical occurrences of retear. The inter-reader weighted kappa value for the visual grading was 0.74 when averaged across three reader pairs (0.70-0.77 for individual reader pairs). The weighted kappa value between the visual grading and the reference standard ranged from 0.75 to 0.83. There was a significant difference in retear rates of the rotator cuff between the 3 visual grades of supraspinatus muscle atrophy on MRI in univariable analysis (p < 0.001), but not in multivariable analysis (p = 0.026). The 3-point visual grading system may be a feasible method to assess the severity of supraspinatus muscle atrophy on MRI and assist in the clinical management of patients with rotator cuff tear.

  14. Final Report: A CdZnTe detector for MRI-compatible SPECT Systems

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Ling-Jian

    2012-12-27

    The key objective of this project is to develop the enabling technology for future MRI-compatible nuclear (e.g. SPECT) imaging system, and to demonstrate the feasibility of performing simultaneous MR and SPECT imaging studies of the same object. During the past three years, we have developed (a) a MRI-compatible ultrahigh resolution gamma ray detector and associated readout electronics, (b) a theoretical approach for modeling the effect of strong magnetic field on SPECT image quality, and (c) a maximum-likelihood (ML) based reconstruction routine with correction for the MR-induced distortion. With this support, we have also constructed a four-head MR-compatible SPECT system and tested the system inside a 3-T clinical MR-scanner located on UI campus. The experimental results obtained with this system have clearly demonstrated that sub-500um spatial resolution can be achieved with a SPECT system operated inside a 3-T MRI scanner. During the past three years, we have accomplished most of the major objectives outlined in the original proposal. These research efforts have laid out a solid foundation the development of future MR-compatible SPECT systems for both pre-clinical and clinical imaging applications.

  15. Evaluasi Pemanfaatan Wireless Internet Protocol Access System di Kota Malang

    Directory of Open Access Journals (Sweden)

    Ahmad Budi Setiawan

    2012-03-01

    Full Text Available WIPAS (Wireless Internet Protocol Accsess System adalah salah satu teknologi pita lebar (broadband yang terbaru. Teknologi tersebut dikembangkan berdasarkan model point-to-multipoint access system pada jaringan nirkabel tetap atau Fixed Wireless Access (FWA dengan memanfaatkan pita frekuensi 26-GHz. Dengan besarnya pita frekuensi yang digunakan, teknologi WIPAS dapat menampung kapasitas akses untuk lalu lintas jaringan yang sangat besar. Dalam penelitian ini akan dikaji dan dievaluasi efektifitas penggunaan teknologi WIPAS melalui kasus pemanfaatan teknologi WIPAS untuk pemberdayaan komunitas di kota Malang. Dalam penelitian ini juga akan dideskripsikan pemanfaatan teknologi WIPAS untuk melihat manfaat penggunaan teknologi tersebut. Penelitian ini dilakukan dengan metode kualitatif dengan melakukan evaluasi terhadap infrastruktur yang telah dibangun untuk melihat efektifitas pemanfaatan WIPAS. Hasil penelitian ini adalah sebuah kajian evaluatif tentang pemanfaatan WIPAS di kota Malang dan rekomendasi untuk implementasi lebih lanjut.

  16. MRI Guided Brain Stimulation without the Use of a Neuronavigation System

    Directory of Open Access Journals (Sweden)

    Ehsan Vaghefi

    2015-01-01

    Full Text Available A key issue in the field of noninvasive brain stimulation (NIBS is the accurate localization of scalp positions that correspond to targeted cortical areas. The current gold standard is to combine structural and functional brain imaging with a commercially available “neuronavigation” system. However, neuronavigation systems are not commonplace outside of specialized research environments. Here we describe a technique that allows for the use of participant-specific functional and structural MRI data to guide NIBS without a neuronavigation system. Surface mesh representations of the head were generated using Brain Voyager and vectors linking key anatomical landmarks were drawn on the mesh. Our technique was then used to calculate the precise distances on the scalp corresponding to these vectors. These calculations were verified using actual measurements of the head and the technique was used to identify a scalp position corresponding to a brain area localized using functional MRI.

  17. Design, Development, and Evaluation of a Master-Slave Surgical System for Breast Biopsy under Continuous MRI.

    Science.gov (United States)

    Yang, Bo; Roys, Steven; Tan, U-Xuan; Philip, Mathew; Richard, Howard; Gullapalli, Rao; Desai, Jaydev P

    2014-04-01

    Magnetic Resonance Imaging (MRI) provides superior soft-tissue contrast in cancer diagnosis compared to other imaging modalities. However, the strong magnetic field inside the MRI bore along with limited scanner bore size poses significant challenges. Since current approaches in breast biopsy using MR images is primarily a blind targeting approach, it is necessary to develop a MRI-compatible robot that can avoid multiple needle insertions into the breast tissue. This MRI-compatible robotic system could potentially lead to improvement in the targeting accuracy and reduce sampling errors. A master-slave surgical system has been developed comprising of a MRI-compatible slave robot which consists of one piezo motor and five pneumatic cylinders connected by long pneumatic transmission lines. The slave robot follows the configuration of the master robot, which provides an intuitive manipulation interface for the physician and operates inside the MRI bore to adjust the needle position and orientation and perform needle insertion task. Based on the MRI experiments using the slave robot, there was no significant distortion in the images and hence the slave robot can be safely operated inside the MRI with minimal loss in signal-to-noise ratio (SNR). Ex vivo and in vivo experiments have been conducted to evaluate the performance of the master-slave surgical system.

  18. Central nervous system lesions in adult T-cell leukaemia: MRI and pathology

    Energy Technology Data Exchange (ETDEWEB)

    Kitajima, M.; Korogi, Y.; Shigematsu, Y.; Liang, L.; Takahashi, M. [Department of Radiology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Matsuoka, M. [Second Division of Internal Medicine, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Yamamoto, T. [Department of Pathology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Jhono, M. [Department of Dermatology, Kumamoto University School of Medicine, Honjo, Kumamoto (Japan); Eto, K. [The National Institute for Minamata Disease, Minamata (Japan)

    2002-07-01

    Adult T-cell leukaemia (ATL) is a T-cell lymphoid neoplasm caused by human T-cell leukaemia virus type I (HTLV-I). Radiological findings in central nervous system (CNS) involvement have not been well characterised. We reviewed the MRI of 18 patients with ATL who developed new neurological symptoms or signs, and pathology specimens from a 53-year-old woman who died of ATL. MRI findings were divided into three categories: definite, probable, and other abnormal. Definite and probable findings were defined as ATL-related. The characteristic findings were multiple parenchymal masses with or without contrast enhancement adjacent to cerebrospinal fluid (CSF) spaced and the deep grey matter of both cerebral hemispheres, plus leptomeningeal lesion. One patient had both cerebral and spinal cord lesions. Other abnormal findings in eight patients included one case of leukoencephalopathy caused by methotrexate. The histology findings consisted of clusters of tumour cells along perivascular spaces, and scattered infiltration of the parenchyma, with nests of tumour cells. Leptomeningeal infiltration by tumour spread into the parenchyma and secondary degeneration of the neuronal tracts was observed. MRI was useful for detecting CNS invasion by ATL and differentiating it from other abnormalities. The MRI findings seemed to correlate well with the histological changes. (orig.)

  19. MRI classification system (MRICS) for children with cerebral palsy: development, reliability, and recommendations.

    Science.gov (United States)

    Himmelmann, Kate; Horber, Veronka; De La Cruz, Javier; Horridge, Karen; Mejaski-Bosnjak, Vlatka; Hollody, Katalin; Krägeloh-Mann, Ingeborg

    2017-01-01

    To develop and evaluate a classification system for magnetic resonance imaging (MRI) findings of children with cerebral palsy (CP) that can be used in CP registers. The classification system was based on pathogenic patterns occurring in different periods of brain development. The MRI classification system (MRICS) consists of five main groups: maldevelopments, predominant white matter injury, predominant grey matter injury, miscellaneous, and normal findings. A detailed manual for the descriptions of these patterns was developed, including test cases (www.scpenetwork.eu/en/my-scpe/rtm/neuroimaging/cp-neuroimaging/). A literature review was performed and MRICS was compared with other classification systems. An exercise was carried out to check applicability and interrater reliability. Professionals working with children with CP or in CP registers were invited to participate in the exercise and chose to classify either 18 MRIs or MRI reports of children with CP. Classification systems in the literature were compatible with MRICS and harmonization possible. Interrater reliability was found to be good overall (k=0.69; 0.54-0.82) among the 41 participants and very good (k=0.81; 0.74-0.92) using the classification based on imaging reports. Surveillance of Cerebral Palsy in Europe (SCPE) proposes the MRICS as a reliable tool. Together with its manual it is simple to apply for CP registers. © 2016 Mac Keith Press.

  20. Magnetic resonance-guided upper abdominal biopsies in a high-field wide-bore 3-T MRI system: feasibility, handling, and needle artefacts

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, Jens-Peter; Langner, Soenke; Hegenscheid, Katrin; Hosten, Norbert; Puls, Ralf [Ernst Moritz Arndt University of Greifswald, Department of Radiology, Greifswald (Germany); Evert, Matthias [Ernst Moritz Arndt University of Greifswald, Department of Pathology, Greifswald (Germany); Kickhefel, Antje [Siemens Healthcare, Erlangen (Germany)

    2010-10-15

    To investigate the feasibility and handling of abdominal MRI-guided biopsies in a 3-T MRI system. Over a 1-year period, 50 biopsies were obtained in 47 patients with tumours of the upper abdominal organs guided by 3-T MRI with a large-bore diameter of 70 cm. Lesions in liver (47), spleen (1) and kidney (2) were biopsied with a coaxial technique using a 16-G biopsy needle guided by a T1-weighted three-dimensional gradient recalled echo volumetric interpolated breath-hold examination (T1w-3D-GRE-VIBE) sequence. Sensitivity, specificity, accuracy, complication rate, interventional complexity, room/intervention time and needle artefacts were determined. A sensitivity of 0.93, specificity of 1.0 and accuracy of 0.94 were observed. Three patients required a rebiopsy. There was a minor complications rate of 13.6%, and no major complications were observed. Histopathology revealed 38 malignant lesions, and 3-month follow-up confirmed 9 benign lesions. Mean lesion diameter was 3.4 {+-} 3.1 cm (50% being smaller than 2 cm). Mean needle tract length was 10.8 {+-} 3.3 cm. Median room time was 42.0 {+-} 19.8 min and intervention time 9.3 {+-} 8.1 min. Needle artefact size was about 9-fold greater for perpendicular access versus access parallel to the main magnetic field. Biopsies of the upper abdomen can be performed with great technical success and easy handling because of the large-bore diameter. The MRI-guided biopsy needle had an acceptable susceptibility artefact at 3 T. However future research must aim to reduce the susceptibility effects of the biopsy systems. (orig.)

  1. Evaluation of Brain and Cervical MRI Abnormality Rates in Patients With Systemic Lupus Erythematosus With or Without Neurological Manifestations

    Directory of Open Access Journals (Sweden)

    Seyed Reza Najafizadeh

    2011-11-01

    Full Text Available Background: Central nervous system (CNS involvement has been observed in 14-80% of patients with systemic lupus erythematosus (SLE. Magnetic resonance imaging (MRI is an appropriate method for evaluating CNS involvement in these patients. Clinical manifestations and MRI findings of CNS lupus should be differentiated from other mimicking diseases such as multiple sclerosis (MS.Objectives: The aim of this study was to evaluate the prevalence and extent of brain and cervical cord MRI lesions of lupus patients. The relationship between neurological signs and symptoms and MRI findings were evaluated as well.Patients and Methods: Fifty SLE patients who had been referred to the rheumatology clinic of our hospital within 2009 were included in a cross sectional study. All patients fulfilled the revised 1981 American College of Rheumatology (ACR criteria for SLE. We evaluated the neurological signs and symptoms and brain and cervical MRI findings in these patients.Results: Forty-one patients (82% were female and nine (18% were male. The mean age was 30.1 ± 9.3 years. Twenty eight (56% patients had an abnormal brain MRI. No one showed any abnormality in the cervical MRI. The lesions in 20 patients were similar to demyelinative plaques. Seventeen patients with abnormal brain MRI were neurologically asymptomatic. There was only a significant relationship between neurological motor manifestations and brain MRI abnormal findings.Conclusions: Unlike the brain, cervical MRI abnormality and especially asymptomatic cord involvement in MRI is quite rare in SLE patients. This finding may be helpful to differentiate SLE from other CNS disorders such as MS.

  2. MINIPILOT SOLAR SYSTEM: DESIGN/OPERATION OF SYSTEM AND RESULTS OF NON-SOLAR TESTING AT MRI

    Science.gov (United States)

    Prior to this project, MRI had carried out work for the Environmental Protection Agency (EPA) on the conceptual design of a solar system for solid waste disposal and a follow-on project to study the feasibility of bench-scale testing of desorption of organics from soil with destr...

  3. The "mirror-neuron system" in MS: A 3 tesla fMRI study.

    Science.gov (United States)

    Rocca, M A; Tortorella, P; Ceccarelli, A; Falini, A; Tango, D; Scotti, G; Comi, G; Filippi, M

    2008-01-22

    The mirror neuron system (MNS) is an observation-execution matching system activated, in humans, during action observation, motor learning, and imitation of action. We used functional MRI (fMRI) to investigate the properties of the MNS in patients with multiple sclerosis (MS). Using a 3 tesla scanner, we acquired fMRI in 16 right-handed patients with relapsing-remitting MS and 14 controls. Two motor tasks were studied. The first consisted of repetitive flexion-extension of the last four fingers of the right hand (simple task) alternated to epochs of rest; the second (MNS task) consisted of observation of a movie showing the hand of another subject while performing the same task. During the simple task, compared to controls, patients with MS had more significant activations of the contralateral primary sensorimotor cortex and supplementary motor area. During the MNS task, both groups showed the activation of several visual areas, the infraparietal sulcus, and the inferior frontal gyrus (IFG), bilaterally. The IFG and the visual areas were significantly more active in patients than controls. The between-group interaction analysis showed that in patients with MS, part of the regions of the MNS were more active also during the simple task. This study suggests increased activation of the mirror neuron system in patients with multiple sclerosis (MS) with a normal level of function and widespread CNS damage. The potentialities of this system in facilitating clinical recovery in patients with MS and other neurologic conditions should be investigated.

  4. Privacy and Access Control for IHE-Based Systems

    Science.gov (United States)

    Katt, Basel; Breu, Ruth; Hafner, Micahel; Schabetsberger, Thomas; Mair, Richard; Wozak, Florian

    Electronic Health Record (EHR) is the heart element of any e-health system, which aims at improving the quality and efficiency of healthcare through the use of information and communication technologies. The sensitivity of the data contained in the health record poses a great challenge to security. In this paper we propose a security architecture for EHR systems that are conform with IHE profiles. In this architecture we are tackling the problems of access control and privacy. Furthermore, a prototypical implementation of the proposed model is presented.

  5. Licensed Shared Access System Possibilities for Public Safety

    Directory of Open Access Journals (Sweden)

    Kalle Lähetkangas

    2016-01-01

    Full Text Available We investigate the licensed shared access (LSA concept based spectrum sharing ideas between public safety (PS and commercial radio systems. While the concept of LSA has been well developed, it has not been thoroughly investigated from the public safety (PS users’ point of view, who have special requirements and also should benefit from the concept. Herein, we discuss the alternatives for spectrum sharing between PS and commercial systems. In particular, we proceed to develop robust solutions for LSA use cases where connections to the LSA system may fail. We simulate the proposed system with different failure models. The results show that the method offers reliable LSA spectrum sharing in various conditions assuming that the system parameters are set properly. The paper gives guidelines to set these parameters.

  6. Authorisation and access control for electronic health record systems.

    Science.gov (United States)

    Blobel, Bernd

    2004-03-31

    Enabling the shared care paradigm, centralised or even decentralised electronic health record (EHR) systems increasingly become core applications in hospital information systems and health networks. For realising multipurpose use and reuse as well as inter-operability at knowledge level, EHR have to meet special architectural requirements. The component-oriented and model-based architecture should meet international standards. Especially in extended health networks realising inter-organisational communication and co-operation, authorisation cannot be organised at user level anymore. Therefore, models, methods and tools must be established to allow formal and structured policy definition, policy agreements, role definition, authorisation and access control. Based on the author's international engagement in EHR architecture and security standards referring to the revision of CEN ENV 13606, the GEHR/open EHR approach, HL7 and CORBA, models for health-specific and EHR-related roles, for authorisation management and access control have been developed. The basic concept is the separation of structural roles defining organisational entity-to-entity relationships and enabling specific acts on the one hand, and functional roles bound to specific activities and realising rights and duties on the other hand. Aggregation of organisational, functional, informational and technological components follows specific rules. Using UML and XML, the principles as well as some examples for analysis, design, implementation and maintenance of policy and authorisation management as well as access control have been practically implemented.

  7. Volumetric MRI of the limbic system: anatomic determinants

    Energy Technology Data Exchange (ETDEWEB)

    Bilir, E.; Craven, W.; Hugg, J.; Gilliam, F.; Martin, R.; Faught, E.; Kuzniecky, R. [UAB Epilepsy Center, Department of Neurology, University of Alabama at Birmingham, Birmingham, AL (United States)

    1998-03-01

    The limbic system comprises the hippocampal formation, fornix, mamillary bodies, thalamus, and other integrated structures. It is involved in complex functions including memory and emotion and in diseases such as temporal lobe epilepsy. Volume measurements of the amygdala and hippocampus have been used reliably to study patients with temporal lobe epilepsy but have not extended to other limbic structures. We performed volume measurements of hippocampus, amygdala, fornix and mamillary bodies in healthy individuals. Measurements of the amygdala, hippocampus, fornix and mamillary bodies revealed significant differences in volume between right and left sides (P < 0.001). The intraclass coefficient of variation for measurements was high for all structures except the mamillary bodies. Qualitative image assessment of the same structures revealed no asymmetries between the hemispheres. This technique can be applied to the study of disorders affecting the limbic system. (orig.) With 4 figs., 2 tabs., 23 refs.

  8. Functional MRI of the olfactory system in conscious dogs.

    Directory of Open Access Journals (Sweden)

    Hao Jia

    Full Text Available We depend upon the olfactory abilities of dogs for critical tasks such as detecting bombs, landmines, other hazardous chemicals and illicit substances. Hence, a mechanistic understanding of the olfactory system in dogs is of great scientific interest. Previous studies explored this aspect at the cellular and behavior levels; however, the cognitive-level neural substrates linking them have never been explored. This is critical given the fact that behavior is driven by filtered sensory representations in higher order cognitive areas rather than the raw odor maps of the olfactory bulb. Since sedated dogs cannot sniff, we investigated this using functional magnetic resonance imaging of conscious dogs. We addressed the technical challenges of head motion using a two pronged strategy of behavioral training to keep dogs' head as still as possible and a single camera optical head motion tracking system to account for residual jerky movements. We built a custom computer-controlled odorant delivery system which was synchronized with image acquisition, allowing the investigation of brain regions activated by odors. The olfactory bulb and piriform lobes were commonly activated in both awake and anesthetized dogs, while the frontal cortex was activated mainly in conscious dogs. Comparison of responses to low and high odor intensity showed differences in either the strength or spatial extent of activation in the olfactory bulb, piriform lobes, cerebellum, and frontal cortex. Our results demonstrate the viability of the proposed method for functional imaging of the olfactory system in conscious dogs. This could potentially open up a new field of research in detector dog technology.

  9. A Rewritable, Random-Access DNA-Based Storage System

    Science.gov (United States)

    Tabatabaei Yazdi, S. M. Hossein; Yuan, Yongbo; Ma, Jian; Zhao, Huimin; Milenkovic, Olgica

    2015-09-01

    We describe the first DNA-based storage architecture that enables random access to data blocks and rewriting of information stored at arbitrary locations within the blocks. The newly developed architecture overcomes drawbacks of existing read-only methods that require decoding the whole file in order to read one data fragment. Our system is based on new constrained coding techniques and accompanying DNA editing methods that ensure data reliability, specificity and sensitivity of access, and at the same time provide exceptionally high data storage capacity. As a proof of concept, we encoded parts of the Wikipedia pages of six universities in the USA, and selected and edited parts of the text written in DNA corresponding to three of these schools. The results suggest that DNA is a versatile media suitable for both ultrahigh density archival and rewritable storage applications.

  10. A Comprehensive System for Monitoring Urban Accessibility in Smart Cities.

    Science.gov (United States)

    Mora, Higinio; Gilart-Iglesias, Virgilio; Pérez-Del Hoyo, Raquel; Andújar-Montoya, María Dolores

    2017-08-09

    The present work discusses the possibilities offered by the evolution of Information and Communication Technologies with the aim of designing a system to dynamically obtain knowledge of accessibility issues in urban environments. This system is facilitated by technology to analyse the urban user experience and movement accessibility, which enabling accurate identification of urban barriers and monitoring its effectiveness over time. Therefore, the main purpose of the system is to meet the real needs and requirements of people with movement disabilities. The information obtained can be provided as a support service for decision-making to be used by city government, institutions, researchers, professionals and other individuals of society in general to improve the liveability and quality of the lives of citizens. The proposed system is a means of social awareness that makes the most vulnerable groups of citizens visible by involving them as active participants. To perform and implement the system, the latest communication and positioning technologies for smart sensing have been used, as well as the cloud computing paradigm. Finally, to validate the proposal, a case study has been presented using the university environment as a pre-deployment step in urban environments.

  11. Assessment of three different software systems in the evaluation of dynamic MRI of the breast

    Energy Technology Data Exchange (ETDEWEB)

    Kurz, K.D. [Department of Radiology, Stavanger University Hospital, Postbox 8100, Stavanger (Norway)], E-mail: kurk@sus.no; Steinhaus, D. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: Daniele.Steinhaus@med.uni-duesseldorf.de; Klar, V. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: verena.klar@uni-duesseldorf.de; Cohnen, M. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: cohnen@med.uni-duesseldorf.de; Wittsack, H.J. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: wittsack@uni-duesseldorf.de; Saleh, A. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: saleh@uni-duesseldorf.de; Moedder, U. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: moedder@med.uni-duesseldorf.de; Blondin, D. [Institute of Daignostic Radiology, Duesseldorf University Hospital, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: blondin@med.uni-duesseldorf.de

    2009-02-15

    Objective: The aim was to compare the diagnostic performance and handling of dynamic contrast-enhanced MRI of the breast with two commercial software solutions ('CADstream' and '3TP') and one self-developed software system ('Mammatool'). Materials and methods: Identical data sets of dynamic breast MRI from 21 patients were evaluated retrospectively with all three software systems. The exams were classified according to the BI-RADS classification. The number of lesions in the parametric mapping was compared to histology or follow-up of more than 2 years. In addition, 25 quality criteria were judged by 3 independent investigators with a score from 0 to 5. Statistical analysis was performed to document the quality ranking of the different software systems. Results: There were 9 invasive carcinomas, one pure DCIS, one papilloma, one radial scar, three histologically proven changes due to mastopathy, one adenosis and two fibroadenomas. Additionally two patients with enhancing parenchyma followed with MRI for more than 3 years and one scar after breast conserving therapy were included. All malignant lesions were classified as BI-RADS 4 or 5 using all software systems and showed significant enhancement in the parametric mapping. 'CADstream' showed the best score on subjective quality criteria. '3TP' showed the lowest number of false-positive results. 'Mammatool' produced the lowest number of benign tissues indicated with parametric overlay. Conclusion: All three software programs tested were adequate for sensitive and efficient assessment of dynamic MRI of the breast. Improvements in specificity may be achievable.

  12. Central nervous system involvement in incontinentia pigmenti: cranial MRI of two siblings

    Energy Technology Data Exchange (ETDEWEB)

    Aydingoez, Ue.; Midia, M. [Department of Radiology, Hacettepe University School of Medicine, Ankara (Turkey)

    1998-06-01

    Incontinentia pigmenti is an uncommon neurocutaneous syndrome characterised by skin lesions, dental and ocular abnormalities and central nervous system involvement. We report the cranial MRI findings in two sisters with this condition. These include hypoplasia of the corpus callosum, enlargement of the lateral ventricles and periventricular white-matter lesions. One girl also had unilateral microphthalmia and rostral agenesis of the corpus callosum, a feature not previously described. (orig.) With 2 figs., 9 refs.

  13. Use of CDMA access technology in mobile satellite systems

    Science.gov (United States)

    Ramasastry, Jay; Wiedeman, Bob

    1995-01-01

    Use of Code Division Multiple Access (CDMA) technology in terrestrial wireless systems is fairly well understood. Similarly, design and operation of Power Control in a CDMA-based system in a terrestrial environment is also well established. Terrestrial multipath characteristics, and optimum design of the CDMA receiver to deal with multipath and fading conditions are reliably established. But the satellite environment is different. When the CDMA technology is adopted to the satellite environment, other design features need to be incorporated (for example; interleaving, open-loop and closed-loop power control design, diversity characteristics) to achieve comparable level of system performance. In fact, the GLOBALSTAR LEO/MSS system has incorporated all these features. Contrary to some published reports, CDMA retains the advantages in the satellite environment that are similar to those achieved in the terrestrial environment. This document gives a description of the CDMA waveform and other design features adopted for mobile satellite applications.

  14. A novel optically transparent RF shielding for fully integrated PET/MRI systems.

    Science.gov (United States)

    Parl, C; Kolb, A; Schmid, A M; Wehrl, H F; Disselhorst, J A; Soubiran, P D; Stricker-Shaver, D; Pichler, B J

    2017-09-01

    Preclinical imaging benefits from simultaneous acquisition of high-resolution anatomical and molecular data. Additionally, PET/MRI systems can provide functional PET and functional MRI data. To optimize PET sensitivity, we propose a system design that fully integrates the MRI coil into the PET system. This allows positioning the scintillators near the object but requires an optimized design of the MRI coil and PET detector. It further requires a new approach in realizing the radiofrequency (RF) shielding. Thus, we propose the use of an optically transparent RF shielding material between the PET scintillator and the light sensor, suppressing the interference between both systems. We evaluated two conductive foils (ITO, 9900) and a wire mesh. The PET performance was tested on a dual-layer scintillator consisting of 12  ×  12 LSO matrices, shifted by half a pitch. The pixel size was 0.9  ×  0.9 mm(2); the lengths were 10.0 mm and 5.0 mm, respectively. For a light sensor, we used a 4  ×  4 SiPM array. The RF attenuation was measured from 320 kHz to 420 MHz using two pick-up coils. MRI-compatibility and shielding effect of the materials were evaluated with an MRI system. The average FWHM energy resolution at 511 keV of all 144 crystals of the layer next to the SiPM was deteriorated from 15.73  ±  0.24% to 16.32  ±  0.13%, 16.60  ±  0.25%, and 19.16  ±  0.21% by the ITO foil, 9900 foil, mesh material, respectively. The average peak-to-valley ratio of the PET detector changed from 5.77  ±  0.29 to 4.50  ±  0.39, 4.78  ±  0.48, 3.62  ±  0.16, respectively. The ITO, 9900, mesh attenuated the scintillation light by 11.3  ±  1.6%, 11.0  ±  1.8%, 54.3  ±  0.4%, respectively. To attenuate the RF from 20 MHz to 200 MHz, mesh performed better than copper. The results show that an RF shielding material that is sufficiently transparent for

  15. A novel optically transparent RF shielding for fully integrated PET/MRI systems

    Science.gov (United States)

    Parl, C.; Kolb, A.; Schmid, A. M.; Wehrl, H. F.; Disselhorst, J. A.; Soubiran, P. D.; Stricker-Shaver, D.; Pichler, B. J.

    2017-09-01

    Preclinical imaging benefits from simultaneous acquisition of high-resolution anatomical and molecular data. Additionally, PET/MRI systems can provide functional PET and functional MRI data. To optimize PET sensitivity, we propose a system design that fully integrates the MRI coil into the PET system. This allows positioning the scintillators near the object but requires an optimized design of the MRI coil and PET detector. It further requires a new approach in realizing the radiofrequency (RF) shielding. Thus, we propose the use of an optically transparent RF shielding material between the PET scintillator and the light sensor, suppressing the interference between both systems. We evaluated two conductive foils (ITO, 9900) and a wire mesh. The PET performance was tested on a dual-layer scintillator consisting of 12  ×  12 LSO matrices, shifted by half a pitch. The pixel size was 0.9  ×  0.9 mm2 the lengths were 10.0 mm and 5.0 mm, respectively. For a light sensor, we used a 4  ×  4 SiPM array. The RF attenuation was measured from 320 kHz to 420 MHz using two pick-up coils. MRI-compatibility and shielding effect of the materials were evaluated with an MRI system. The average FWHM energy resolution at 511 keV of all 144 crystals of the layer next to the SiPM was deteriorated from 15.73  ±  0.24% to 16.32  ±  0.13%, 16.60  ±  0.25%, and 19.16  ±  0.21% by the ITO foil, 9900 foil, mesh material, respectively. The average peak-to-valley ratio of the PET detector changed from 5.77  ±  0.29 to 4.50  ±  0.39, 4.78  ±  0.48, 3.62  ±  0.16, respectively. The ITO, 9900, mesh attenuated the scintillation light by 11.3  ±  1.6%, 11.0  ±  1.8%, 54.3  ±  0.4%, respectively. To attenuate the RF from 20 MHz to 200 MHz, mesh performed better than copper. The results show that an RF shielding material that is sufficiently transparent for

  16. MRI in central nervous system infections: A simplified patterned approach

    Institute of Scientific and Technical Information of China (English)

    Krithika; Rangarajan; Chandan; J; Das; Atin; Kumar; Arun; Kumar; Gupta

    2014-01-01

    Recognition and characterization of central nervous system infections poses a formidable challenge to the neuro-radiologist.Imaging plays a vital role,the lesions typically being relatively inaccessible to tisue sampling.The results of an accurate diagnosis are endlessly re-warding,given the availability of excellent pharmaco-logical regimen.The availability of numerous magnetic resonance(MR)sequences which provide functional and molecular information is a powerful tool in the hands of the radiologist.However,the plethora of se-quences and the possibilities on each sequence is also intimidating,and often confusing as well as time con-suming.While a large number of reviews have already described in detail the possible imaging findings in each infection,we intend to classify infections based on their imaging characteristics.In this review we describe an algorithm for first classifying the imaging findings into patterns based on basic MR sequences(T1,T2 and enhancement pattern with Gadolinium),and then sub-classify them based on more advanced molecular and functional sequences(Diffusion,Perfusion,Susceptibili-ty imaging,MR Spectroscopy).This patterned approachis intended as a guide to radiologists in-training and in-practice for quickly narrowing their list of differentials when faced with a clinical challenge.The entire content of the article has also been summarised in the form of flow-charts for the purpose of quick reference.

  17. Towards Voluntary Interoperable Open Access Licenses for the Global Earth Observation System of Systems (GEOSS)

    NARCIS (Netherlands)

    Onsrud, H.; Campbell, J.; Van Loenen, B.

    2010-01-01

    Access to earth observation data has become critically important for the wellbeing of society. A major impediment to achieving widespread sharing of earth observation data is lack of an operational web-wide system that is transparent and consistent in allowing users to legally access and use the ear

  18. Liquid-state carbon-13 hyperpolarization generated in an MRI system for fast imaging

    Science.gov (United States)

    Schmidt, A. B.; Berner, S.; Schimpf, W.; Müller, C.; Lickert, T.; Schwaderlapp, N.; Knecht, S.; Skinner, J. G.; Dost, A.; Rovedo, P.; Hennig, J.; von Elverfeldt, D.; Hövener, J.-B.

    2017-03-01

    Hyperpolarized (HP) tracers dramatically increase the sensitivity of magnetic resonance imaging (MRI) to monitor metabolism non-invasively and in vivo. Their production, however, requires an extra polarizing device (polarizer) whose complexity, operation and cost can exceed that of an MRI system itself. Furthermore, the lifetime of HP tracers is short and some of the enhancement is lost during transfer to the application site. Here, we present the production of HP tracers in water without an external polarizer: by Synthesis Amid the Magnet Bore, A Dramatically Enhanced Nuclear Alignment (SAMBADENA) is achieved within seconds, corresponding to a hyperpolarization of ~20%. As transfer of the tracer is no longer required, SAMBADENA may permit a higher polarization at the time of detection at a fraction of the cost and complexity of external polarizers. This development is particularly promising in light of the recently extended portfolio of biomedically relevant para-hydrogen-tracers and may lead to new diagnostic applications.

  19. PET/MRI of central nervous system: current status and future perspective

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhen Lu; Zhang, Long Jiang [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China)

    2016-10-15

    Imaging plays an increasingly important role in the early diagnosis, prognosis prediction and therapy response evaluation of central nervous system (CNS) diseases. The newly emerging hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) can perform ''one-stop-shop'' evaluation, including anatomic, functional, biochemical and metabolic information, even at the molecular level, for personalised diagnoses and treatments of CNS diseases. However, there are still several problems to be resolved, such as appropriate PET detectors, attenuation correction and so on. This review will introduce the basic physical principles of PET/MRI and its potential clinical applications in the CNS. We also provide the future perspectives for this field. (orig.)

  20. Third Degree Skin Burns Caused by an MRI Compatible Electrocardiographic Monitoring System

    DEFF Research Database (Denmark)

    Brix, Lau; Isaksen, Christin Rosendahl Graff; Kristensen, Birgitte Hornbæk;

    . Positioning of the ECG module in the imaging plane may contribute to heating of the leads due to this effect [3,4]. As this was the case, this may have contributed to the bruns. Furthermore, we believe that the burns were actually caused by the direct skin contact with the leads and a marginal crossing...... of the assigned compatibility specifications of the leads due to the use of TFE sequences with high SAR values. MRI compatible monitoring systems are only safe when used with proper care. The presented burn cases may have been avoided if space had been provided between the ECG leads and the skin using a cloth......Introduction: The combination of increased magnetic field strength, field gradients and RF power, augments the risk of tissue heating in patients undergoing an MRI examination. This is especially important when the patients have implants or when external devices are in direct contact with the skin...

  1. Access Control in Decentralised Publish/Subscribe Systems

    Directory of Open Access Journals (Sweden)

    Lauri I.W. Pesonen

    2007-04-01

    Full Text Available Publish/subscribe has emerged as an attractive communication paradigm for building Internet-wide distributed systems by decoupling message senders from receivers. Large scale publish/subscribe systems are likely to employ components of the event transport network owned by cooperating, but independent organisations. As the number of participants in the network increases, security becomes an increasing concern. So far most of the research on publish/subscribe has focused on efficient event routing, event filtering, and composite event detection. Very little research has been published regarding securing publish/subscribe systems. This paper extends our previous work to present and evaluate a secure multi-domain publish/subscribe infrastructure that supports and enforces fine-grained access control over the individual attributes of event types.

  2. KneeTex: an ontology-driven system for information extraction from MRI reports.

    Science.gov (United States)

    Spasić, Irena; Zhao, Bo; Jones, Christopher B; Button, Kate

    2015-01-01

    In the realm of knee pathology, magnetic resonance imaging (MRI) has the advantage of visualising all structures within the knee joint, which makes it a valuable tool for increasing diagnostic accuracy and planning surgical treatments. Therefore, clinical narratives found in MRI reports convey valuable diagnostic information. A range of studies have proven the feasibility of natural language processing for information extraction from clinical narratives. However, no study focused specifically on MRI reports in relation to knee pathology, possibly due to the complexity of knee anatomy and a wide range of conditions that may be associated with different anatomical entities. In this paper we describe KneeTex, an information extraction system that operates in this domain. As an ontology-driven information extraction system, KneeTex makes active use of an ontology to strongly guide and constrain text analysis. We used automatic term recognition to facilitate the development of a domain-specific ontology with sufficient detail and coverage for text mining applications. In combination with the ontology, high regularity of the sublanguage used in knee MRI reports allowed us to model its processing by a set of sophisticated lexico-semantic rules with minimal syntactic analysis. The main processing steps involve named entity recognition combined with coordination, enumeration, ambiguity and co-reference resolution, followed by text segmentation. Ontology-based semantic typing is then used to drive the template filling process. We adopted an existing ontology, TRAK (Taxonomy for RehAbilitation of Knee conditions), for use within KneeTex. The original TRAK ontology expanded from 1,292 concepts, 1,720 synonyms and 518 relationship instances to 1,621 concepts, 2,550 synonyms and 560 relationship instances. This provided KneeTex with a very fine-grained lexico-semantic knowledge base, which is highly attuned to the given sublanguage. Information extraction results were evaluated

  3. An augmented reality navigation system for pediatric oncologic surgery based on preoperative CT and MRI images.

    Science.gov (United States)

    Souzaki, Ryota; Ieiri, Satoshi; Uemura, Munenori; Ohuchida, Kenoki; Tomikawa, Morimasa; Kinoshita, Yoshiaki; Koga, Yuhki; Suminoe, Aiko; Kohashi, Kenichi; Oda, Yoshinao; Hara, Toshiro; Hashizume, Makoto; Taguchi, Tomoaki

    2013-12-01

    In pediatric endoscopic surgery, a limited view and lack of tactile sensation restrict the surgeon's abilities. Moreover, in pediatric oncology, it is sometimes difficult to detect and resect tumors due to the adhesion and degeneration of tumors treated with multimodality therapies. We developed an augmented reality (AR) navigation system based on preoperative CT and MRI imaging for use in endoscopic surgery for pediatric tumors. The patients preoperatively underwent either CT or MRI with body surface markers. We used an optical tracking system to register the reconstructed 3D images obtained from the CT and MRI data and body surface markers during surgery. AR visualization was superimposed with the 3D images projected onto captured live images. Six patients underwent surgery using this system. The median age of the patients was 3.5 years. Two of the six patients underwent laparoscopic surgery, two patients underwent thoracoscopic surgery, and two patients underwent laparotomy using this system. The indications for surgery were local recurrence of a Wilms tumor in one case, metastasis of rhabdomyosarcoma in one case, undifferentiated sarcoma in one case, bronchogenic cysts in two cases, and hepatoblastoma in one case. The average tumor size was 22.0±14.2 mm. Four patients were treated with chemotherapy, three patients were treated with radiotherapy before surgery, and four patients underwent reoperation. All six tumors were detected using the AR navigation system and successfully resected without any complications. The AR navigation system is very useful for detecting the tumor location during pediatric surgery, especially for endoscopic surgery. Crown Copyright © 2013. All rights reserved.

  4. Visualization of the eloquent motor system by integration of MEG, functional, and anisotropic diffusion-weighted MRI in functional neuronavigation.

    Science.gov (United States)

    Kamada, Kyousuke; Houkin, Kiyohiro; Takeuchi, Fumiya; Ishii, Nobuaki; Ikeda, Jun; Sawamura, Yutaka; Kuriki, Shinya; Kawaguchi, Hideaki; Iwasaki, Yoshinobu

    2003-05-01

    In this study, we visualized the eloquent motor system including the somatosensory-motor cortex and corticospinal tract on a neuronavigation system, integrating magnetoencephalography (MEG), functional magnetic resonance imaging (fMRI), and anisotropic diffusion-weighted MRI (ADWI). Four patients with brain lesions adjacent to the eloquent motor system were studied. Motor-evoked responses (MER) by finger-tapping paradigm were acquired with a 1.5-Tesla MR scanner, and somatosensory-evoked magnetic fields (SEF) by median nerve stimulation were measured with a 204-channel MEG system. In the same fMRI examination, ADWI and anatomic three-dimensional T1-weighted imaging (3-D MRI) were obtained. Activated areas of MER, estimated SEF dipoles, and the corticospinal tract on ADWI were coregistered to 3-D MRI, and the combined MR data were transferred to a neuronavigation system (functional neuronavigation). Intraoperative recording of cortical somatosensory-evoked potentials was performed for confirmation of the central sulcus. Combination of fMRI and MEG enabled firm identification of the central sulcus. Functional neuronavigation facilitated extensive tumor resection, having the advantage of sparing the motor cortex and corticospinal tract in all cases. The proposed functional neuronavigation allows neurosurgeons to perform effective and maximal resection of brain lesions, identifying and sparing eloquent cortical components and their subcortical connections. Potential clinical application of this technique is discussed.

  5. A recently developed MRI scoring system for hand osteoarthritis: its application in a clinical setting.

    Science.gov (United States)

    Ramonda, Roberta; Favero, Marta; Vio, Stefania; Lacognata, Carmelo; Frallonardo, Paola; Belluzzi, Elisa; Campana, Carla; Lorenzin, Mariagrazia; Ortolan, Augusta; Angelini, Federico; Piccoli, Antonio; Oliviero, Francesca; Punzi, Leonardo

    2016-08-01

    This study aimed to apply the recently proposed Oslo hand osteoarthritis magnetic resonance imaging (MRI) scoring system to evaluate MRI findings in a cohort of patients affected by long-standing erosive hand osteoarthritis (EHOA). Eleven female EHOA patients (median 59 [interquartile range 62-52] years, disease duration 9.5 [interquartile range 13-3.75] years) underwent MRI (1.5 T) of the dominant hand, and synovitis, bone marrow lesions (BMLs), joint space narrowing, osteophytes, cysts, malalignment, and erosions were scored using the Oslo scoring system. Intra- and inter-reader reliability were assessed. The patients also underwent X-ray examination, and bone features were evaluated using the same scoring system. Pain and tenderness were assessed during a physical examination. Spearman's non-parametric test was used to analyze the correlations between variables. MRI intra- and inter-reader reliability were found between good and moderate for many features. No statistical differences were found between the radiographs and MRI with regard to detection of JSN, malalignment, and bone erosions. Synovitis was detected in 39.8 % of the 80 joints examined (in a mild form in 80 %), erosions were found in 51.1 %, and BMLs were identified in 20.5 and 23.9 % at the distal and the proximal side, respectively. BMLs at both the proximal and distal ends were correlated with tender joints (BML distal p = 0.0013, BML proximal p = 0.012). The presence of synovitis was correlated with tenderness (p = 0.004) and erosions at both the distal and proximal joints (p = 0.004). The presence of erosions correlated with tender joints (p < 0.01) and the mean visual analog scale (VAS) score (distal p = 0.03, proximal p = 0.01). Synovitis and BMLs were correlated with clinical symptoms in our patients affected with long-standing EHOA.

  6. ISPMER: Integrated system for combined PET, MRI, and electrophysiological recording in somatosensory studies in rats

    Energy Technology Data Exchange (ETDEWEB)

    Shih, Y.-Y. [Institute of Biomedical Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, Taiwan (China); Chen, Y.-Y. [Department of Electrical and Control Engineering, National Chiao-Tung University, Hsinchu, Taiwan (China); Chen, J.-C. [Faculty of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan (China); Department of Education and Research, Taipei City Hospital, Taipei, Taiwan (China); Chang Chen [Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan (China); Jaw, F.-S. [Institute of Biomedical Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, Taiwan (China)], E-mail: jaw@ha.mc.ntu.edu.tw

    2007-10-01

    The present study developed an integrated system for use in combined PET, MRI, and electrophysiological recording in somatosensory studies in rats, called ISPMER. A stereotaxic frame was designed for animal positioning that could be used in all three measurement modalities, and its dimensions complied with the gold standard of the Paxinos and Watson rat brain atlas. A graphical user interface was developed for analyzing the data using several signal processing algorithms. This integrated system provides a novel interface for the recording and processing of three-dimensional neuronal signals in three modalities.

  7. EEG-fMRI based information theoretic characterization of the human perceptual decision system.

    Directory of Open Access Journals (Sweden)

    Dirk Ostwald

    Full Text Available The modern metaphor of the brain is that of a dynamic information processing device. In the current study we investigate how a core cognitive network of the human brain, the perceptual decision system, can be characterized regarding its spatiotemporal representation of task-relevant information. We capitalize on a recently developed information theoretic framework for the analysis of simultaneously acquired electroencephalography (EEG and functional magnetic resonance imaging data (fMRI (Ostwald et al. (2010, NeuroImage 49: 498-516. We show how this framework naturally extends from previous validations in the sensory to the cognitive domain and how it enables the economic description of neural spatiotemporal information encoding. Specifically, based on simultaneous EEG-fMRI data features from n = 13 observers performing a visual perceptual decision task, we demonstrate how the information theoretic framework is able to reproduce earlier findings on the neurobiological underpinnings of perceptual decisions from the response signal features' marginal distributions. Furthermore, using the joint EEG-fMRI feature distribution, we provide novel evidence for a highly distributed and dynamic encoding of task-relevant information in the human brain.

  8. A Tumor-Targeted Nanodelivery System to Improve Early MRI Detection of Cancer

    Directory of Open Access Journals (Sweden)

    Kathleen F. Pirollo

    2006-01-01

    Full Text Available The development of improvements in magnetic resonance imaging (MRI that would enhance sensitivity, leading to earlier detection of cancer and visualization of metastatic disease, is an area of intense exploration. We have devised a tumor-targeting, liposomal nanodelivery platform for use in gene medicine. This systemically administered nanocomplex has been shown to specifically and efficiently deliver both genes and oligonucleotides to primary and metastatic tumor cells, resulting in significant tumor growth inhibition and even tumor regression. Here we examine the effect on MRI of incorporating conventional MRI contrast agent Magnevist® into our anti-transferrin receptor single-chain antibody (TfRscFv liposomal complex. Both in vitro and in an in vivo orthotopic mouse model of pancreatic cancer, we show increased resolution and image intensity with the complexed Magnevist®. Using advanced microscopy techniques (scanning electron microscopy and scanning probe microscopy, we also established that the Magnevist® is in fact encapsulated by the liposome in the complex and that the complex still retains its nanodimensional size. These results demonstrate that this TfRscFv-liposome-Magnevist® nanocomplex has the potential to become a useful tool in early cancer detection.

  9. A Metaheuristically Tuned Interval Type 2 Fuzzy System to Reduce Segmentation Uncertainty in Brain MRI Images.

    Science.gov (United States)

    Taghribi, Abolfazl; Sharifian, Saeed

    2017-09-19

    Precise segmentation of magnetic resonance image (MRI) seems challenging because of the complex structure of the brain, non-uniform field in images, and noise. As a result, decision-making is associated with uncertainty. Fuzzy based approaches have been developed to overcome this problem, though most of them use fuzzy type 1 method, and sometimes contain a pre-processing step. This paper "modified type 2 fuzzy system" (MT2FS) declares a state-of-the-art method to segment MRI images using interval fuzzy type-2. Furthermore, Genetic algorithm has been employed to specify the best values for mean and variance of upper and lower membership functions. This strategy will determine discrimination boundaries for different brain tissues to be less independent from the training set. Finally, the result of fuzzy rules is extracted by using Dempster-Shafer rule combination method. Simulation results demonstrate a satisfactory output on both simulated and real MRI images in comparison with previously conducted research works without the need for a pre-processing stage.

  10. MR-guided discography using an open 1 Tesla MRI system

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, Florian; Bucourt, M. de; Hamm, B.; Teichgraeber, U. [Charite, Humboldt-University Medical School, Department of Radiology, Berlin (Germany); Hartwig, T.; Strube, P.; Putzier, M. [Charite, University Medicine Berlin, Center for Musculoskeletal Surgery, Berlin (Germany); Schnackenburg, B. [Philips Medical Systems, Hamburg (Germany); Chopra, S. [Charite, University Medicine Berlin, Department of General, Visceral, and Transplantation Surgery, Berlin (Germany)

    2011-05-15

    To evaluate the feasibility of MR-guided discography using an open 1 Tesla MRI system. 48 disc segments of 41 patients scheduled for intradiscal thermal treatment, total disc replacement or spondylodesis were examined. A 1.0-T open MRI was used for instrument guidance and imaging. After primary disc puncture under guidance of interactive PDw TSE imaging, 1-2 ml of gadolinium contrast saline mixture was injected into the disc. The occurrence of memory pain during injection was recorded. Axial and sagittal T1w TSE images with and without fat saturation were obtained. All MRI discograms were analysed by two readers, who were blinded to the clinical findings. Overall, the placement of the puncture needle in the targeted disc was accurate under real-time MR guidance. Injections were technically successful in all cases. No major complications occurred. The mean procedure time was 17 min (range 13-34 min). Image quality of contrast-enhanced MR discograms was excellent when using an optimized gadolinium contrast saline mixture of 1:600. Memory pain was detected in 16 out of 48 affected segments. MR-guided discography is accurate and safe. Multiplanar dynamic imaging facilitates the puncture of discs and provides high-quality MR discograms. (orig.)

  11. Effect of a computer-aided diagnosis system on radiologists' performance in grading gliomas with MRI

    Science.gov (United States)

    Hsieh, Kevin Li-Chun; Tsai, Ruei-Je; Teng, Yu-Chuan

    2017-01-01

    The effects of a computer-aided diagnosis (CAD) system based on quantitative intensity features with magnetic resonance (MR) imaging (MRI) were evaluated by examining radiologists' performance in grading gliomas. The acquired MRI database included 71 lower-grade gliomas and 34 glioblastomas. Quantitative image features were extracted from the tumor area and combined in a CAD system to generate a prediction model. The effect of the CAD system was evaluated in a two-stage procedure. First, a radiologist performed a conventional reading. A sequential second reading was determined with a malignancy estimation by the CAD system. Each MR image was regularly read by one radiologist out of a group of three radiologists. The CAD system achieved an accuracy of 87% (91/105), a sensitivity of 79% (27/34), a specificity of 90% (64/71), and an area under the receiver operating characteristic curve (Az) of 0.89. In the evaluation, the radiologists’ Az values significantly improved from 0.81, 0.87, and 0.84 to 0.90, 0.90, and 0.88 with p = 0.0011, 0.0076, and 0.0167, respectively. Based on the MR image features, the proposed CAD system not only performed well in distinguishing glioblastomas from lower-grade gliomas but also provided suggestions about glioma grading to reinforce radiologists’ confidence rating. PMID:28158235

  12. Effective Connectivity Modeling for fMRI: Six Issues and Possible Solutions Using Linear Dynamic Systems

    Directory of Open Access Journals (Sweden)

    Jason Fitzgerald Smith

    2012-01-01

    Full Text Available Analysis of directionally specific or causal interactions between regions in functional magnetic resonance imaging (fMRI data has proliferated. Here we identify six issues with existing effective connectivity methods that need addressed. The issues are discussed within the framework of Linear Dynamic Systems for fMRI (LDSf. The first concerns the use of deterministic models to identify inter-regional effective connectivity. We show that deterministic dynamics are incapable of identifying the trial-to-trial variability typically investigated as the marker of connectivity while stochastic models can capture this variability. The second concerns the simplistic (constant connectivity modeled by most methods. Connectivity parameters of the LDSf model can vary at the same timescale as the input data. Further, extending LDSf to mixtures of multiple models provides more robust connectivity variation. The third concerns the correct identification of the network itself including the number and anatomical origin of the network nodes. Augmentation of the LDSf state space can identify additional nodes of a network. The fourth concerns the locus of the signal used as a node in a network. A novel extension LDSf incorporating sparse canonical correlations can select most relevant voxels from an anatomically defined region based on connectivity. The fifth concerns connection interpretation. Individual parameter differences have received most attention. We present alternative network descriptors of connectivity changes which consider the whole network. The sixth concerns the temporal resolution of fMRI data relative to the timescale of the inter-regional interactions in the brain. LDSf includes an instantaneous connection term to capture connectivity occurring at timescales faster than the data resolution. The LDS framework can also be extended to statistically combine fMRI and EEG data. The LDSf framework is a promising foundation for effective connectivity

  13. The OMERACT psoriatic arthritis magnetic resonance imaging scoring system (PsAMRIS): definitions of key pathologies, suggested MRI sequences, and preliminary scoring system for PsA Hands

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; McQueen, Fiona; Wiell, Charlotte

    2009-01-01

    This article describes a preliminary OMERACT psoriatic arthritis magnetic resonance image scoring system (PsAMRIS) for evaluation of inflammatory and destructive changes in PsA hands, which was developed by the international OMERACT MRI in inflammatory arthritis group. MRI definitions of important...

  14. Accessibility of a Destination-Based Transportation System: A Large Airport Study

    Institute of Scientific and Technical Information of China (English)

    SHI Jing; YING Xiwen

    2008-01-01

    The accessibility of a destination-based transportation system is defined to quantify the perform-ance of transportation systems which access a distinct destination. The access cost is used to reflect the utility of the transportation system including the fatigue and inconvenience in the total cost. The cost is quan-tified by two coefficients which represent the different characteristics of various people. The average cost and the income-relative accessibility are used to describe various aspects of the accessibility and to evaluate the accessibility of a destination-based system. A case study uses data from the Kunming transpor-tation system to evaluate the accessibility of the present city airport. The calibrated coefficients are then used to evaluate the transportation system to the new Kunming international airport. The results show that this transportation accessibility evaluation can be combined with transportation planning to study transporta-tion sub-systems.

  15. Spacelab system analysis: The modified free access protocol: An access protocol for communication systems with periodic and Poisson traffic

    Science.gov (United States)

    Ingels, Frank; Owens, John; Daniel, Steven

    1989-01-01

    The protocol definition and terminal hardware for the modified free access protocol, a communications protocol similar to Ethernet, are developed. A MFA protocol simulator and a CSMA/CD math model are also developed. The protocol is tailored to communication systems where the total traffic may be divided into scheduled traffic and Poisson traffic. The scheduled traffic should occur on a periodic basis but may occur after a given event such as a request for data from a large number of stations. The Poisson traffic will include alarms and other random traffic. The purpose of the protocol is to guarantee that scheduled packets will be delivered without collision. This is required in many control and data collection systems. The protocol uses standard Ethernet hardware and software requiring minimum modifications to an existing system. The modification to the protocol only affects the Ethernet transmission privileges and does not effect the Ethernet receiver.

  16. 77 FR 25525 - Thirteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems.

    Science.gov (United States)

    2012-04-30

    ... Access Control Systems. AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems... Committee 224, Airport Security Access Control Systems DATES: The meeting will be held May 30, 2012, from...

  17. Bluetooth Navigation System using Wi-Fi Access Points

    CERN Document Server

    Agrawal, Rohit

    2012-01-01

    There have been various navigation and tracking systems being developed with the help of technologies like GPS, GSM, Bluetooth, IR, Wi-Fi and Radar. Outdoor positioning systems have been deployed quite successfully using GPS but positioning systems for indoor environments still do not have widespread deployment due to various reasons. Most of these use only a single technology for positioning but using more than one in cooperation with each other is always advantageous for obtaining greater accuracy. Particularly, the ones which use Bluetooth are better since they would enhance the scalability of such a system because of the fact that this technology is in use by the common people so it would always be easy to track them. Moreover it would also reduce the hardware installation cost to some extent. The system that has been introduced here uses Bluetooth primarily for positioning and tracking in combination with Wi-Fi access points. The reason that makes the commercial application of such a system easier and ch...

  18. Hentschel random access tracking system HSG 84.30

    Science.gov (United States)

    Zamzow, Heinz

    1990-08-01

    The development of the Random Access Tracking System was initiated at the University of Muenster, Department of Orthopaedic Physiology by Dr. Theysohn. This system is a real-time high-speed and high-resolution multi-point tracking system. The moving objects are identified with retro-reflective markers which are illuminated by halogen spotlights placed around the camera lens. The video interface generates deflection signals which are fed to unique Random Access Cameras manufactured by Hamamatsu Corporation. These signals perform high speed window scanning and can sample up to 7,500 markers per second. Under certain circumstances this can be increased to 15,000 markers per second. From 1 to 126 markers can be detected in a line scan search mode. Window size may be varied in steps from 0.5% to 4.0% of the field of view. Using a small window it is possible to obtain 1 part in 32,768 in each direction of the field of view. The raw data are reduced to 2-D centroids of the targets. On-line data storage and display are possible using an industry-standard ATPC with DMA interface. Real-time feed-back is also possible. The video interface provides for off-line 3-D reconstructions using the data from two or more synchronized cameras. The system can be adapted to meet the needs of particular applications by modifying sample-rate, data transfer rate, and the number and the dimensions of the windows.

  19. Extraction of the human cerebral ventricular system from MRI: inclusion of anatomical knowledge and clinical perspective

    Science.gov (United States)

    Aziz, Aamer; Hu, Qingmao; Nowinski, Wieslaw L.

    2004-04-01

    The human cerebral ventricular system is a complex structure that is essential for the well being and changes in which reflect disease. It is clinically imperative that the ventricular system be studied in details. For this reason computer assisted algorithms are essential to be developed. We have developed a novel (patent pending) and robust anatomical knowledge-driven algorithm for automatic extraction of the cerebral ventricular system from MRI. The algorithm is not only unique in its image processing aspect but also incorporates knowledge of neuroanatomy, radiological properties, and variability of the ventricular system. The ventricular system is divided into six 3D regions based on the anatomy and its variability. Within each ventricular region a 2D region of interest (ROI) is defined and is then further subdivided into sub-regions. Various strict conditions that detect and prevent leakage into the extra-ventricular space are specified for each sub-region based on anatomical knowledge. Each ROI is processed to calculate its local statistics, local intensity ranges of cerebrospinal fluid and grey and white matters, set a seed point within the ROI, grow region directionally in 3D, check anti-leakage conditions and correct growing if leakage occurs and connects all unconnected regions grown by relaxing growing conditions. The algorithm was tested qualitatively and quantitatively on normal and pathological MRI cases and worked well. In this paper we discuss in more detail inclusion of anatomical knowledge in the algorithm and usefulness of our approach from clinical perspective.

  20. A modular, computer-controlled system for olfactory stimulation in the MRI environment.

    Science.gov (United States)

    Andrieu, Patrice; Bonnans, Vincent; Meneses, Jaime; Millot, Jean-Louis; Moulin, Thierry; Gharbi, Tijani

    2014-03-01

    Although the cerebral networks involved in sensory perception are of general interest in neuroscience, registration of the effects of olfactory stimulation, especially in a magnetic resonance imaging (MRI) environment, presents particular problems and constraints. This article presents details of a reliable and portable system for olfactory stimulation that is modular in design and based on microcontroller technology. It has the following characteristics: (1) It is under software control; (2) the presentation of olfactory stimulation can be synchronized with respiration; (3) it can be manually controlled; and (4) it is fully compatible with an MRI environment. The principle underlying this system is to direct an odor to the subject's nostrils by switching airflow to different odor diffusers. The characteristics of this system were established using (1) ultraviolet (UV) spectroscopy, to measure its response time, and (2) gas chromatography, to measure the repeatability of odor presentation in terms of gas concentration. A response time of 200 ± 25 ms was obtained for the system, and the standard deviations of the gas concentration delivered during stimulation ranged from 1.5% to 22%, depending on the odor, the airflow, and the dilution of the odor used. Since it is portable, controlled by software, and reliable, on the basis of the results we obtained, this system will lend itself to a wide range of applications in olfactory neuroscience.

  1. MRI Artifacts

    Directory of Open Access Journals (Sweden)

    Abed Al Nasser Assi

    2009-12-01

    Full Text Available   "nMagnetic resonance imaging (MRI has become more and more frequently used in medical imaging diagnostic in recent years. Radiologists and technicians working at these systems are relatively often confronted with image artifacts related to the radiowave with strong magnetic in the scanner. Many artifacts may be corrected or modulated through an understanding of their cause. This requires familiarity with scanner design; theory of operation; and image acquisition. The purpose of this review article is to present the most relevant artifacts that arise in MRI scanner, to provide some physical background on the formation of artifacts, and to suggest strategies to reduce or avoid these artifacts. The most frequent artifacts that can occur during MRI scanning are Motion related artifacts; Para-magnetic artifacts; Phase Wrap artifacts; Frequency artifacts; Susceptibility artifacts; Clipping artefact; Chemical Shift artifact and "Zebra" artefact .    "n  

  2. Safety systems and access control in the National Ignition Facility.

    Science.gov (United States)

    Reed, Robert K; Bell, Jayce C

    2013-06-01

    The National Ignition Facility (NIF) is the world's largest and most energetic laser system. The facility has the potential to generate ionizing radiation due to the interaction between the laser beams and target material, with neutrons and gamma rays being produced during deuterium-tritium fusion reactions. To perform these experiments, several types of hazards must be mitigated and controlled to ensure personnel safety. NIF uses a real-time safety system to monitor and mitigate the hazards presented by the facility. The NIF facility Safety Interlock System (SIS) monitors for oxygen deficiency and controls access to the facility preventing exposure to laser light and radiation from the Radiation Generating Devices. It also interfaces to radiation monitoring and other radiological monitoring and alarm systems. The SIS controls permissives to the hazard-generating equipment and annunciates hazard levels in the facility. To do this reliably and safely, the SIS has been designed as a fail-safe system with a proven performance record now spanning over 10 y. This paper discusses the SIS, its design, implementation, operator interfaces, validation/verification, and the hazard mitigation approaches employed in the NIF. A brief discussion of the Failure Modes and Effect Analysis supporting the SIS will also be presented. The paper ends with a general discussion of SIS do's and don'ts and common design flaws that should be avoided in SIS design.

  3. MRI zoo

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    The basic idea was to use MRI to produce a sequence of 3D gray scale image slices of various animals, subsequentlyimaged with a clinical CT system. For this purpose, these animals were used: toad, lungfish, python snake and a horseshoe crab. Each animal was sacrificed according to standard proced...

  4. Framework for monitoring equity in access and health systems ...

    African Journals Online (AJOL)

    paper, proposes a framework for monitoring equity in access and health .... get additional data through in—depth and qualitative studies. Equity and health .... characteristics of HIV infected patients seeking care in relation to access to the Drug ...

  5. Solid cryogen: a cooling system for future MgB2 MRI magnet

    Science.gov (United States)

    Patel, Dipak; Hossain, Md Shahriar Al; Qiu, Wenbin; Jie, Hyunseock; Yamauchi, Yusuke; Maeda, Minoru; Tomsic, Mike; Choi, Seyong; Kim, Jung Ho

    2017-03-01

    An efficient cooling system and the superconducting magnet are essential components of magnetic resonance imaging (MRI) technology. Herein, we report a solid nitrogen (SN2) cooling system as a valuable cryogenic feature, which is targeted for easy usability and stable operation under unreliable power source conditions, in conjunction with a magnesium diboride (MgB2) superconducting magnet. The rationally designed MgB2/SN2 cooling system was first considered by conducting a finite element analysis simulation, and then a demonstrator coil was empirically tested under the same conditions. In the SN2 cooling system design, a wide temperature distribution on the SN2 chamber was observed due to the low thermal conductivity of the stainless steel components. To overcome this temperature distribution, a copper flange was introduced to enhance the temperature uniformity of the SN2 chamber. In the coil testing, an operating current as high as 200 A was applied at 28 K (below the critical current) without any operating or thermal issues. This work was performed to further the development of SN2 cooled MgB2 superconducting coils for MRI applications.

  6. Solid cryogen: a cooling system for future MgB2 MRI magnet

    Science.gov (United States)

    Patel, Dipak; Hossain, Md Shahriar Al; Qiu, Wenbin; Jie, Hyunseock; Yamauchi, Yusuke; Maeda, Minoru; Tomsic, Mike; Choi, Seyong; Kim, Jung Ho

    2017-01-01

    An efficient cooling system and the superconducting magnet are essential components of magnetic resonance imaging (MRI) technology. Herein, we report a solid nitrogen (SN2) cooling system as a valuable cryogenic feature, which is targeted for easy usability and stable operation under unreliable power source conditions, in conjunction with a magnesium diboride (MgB2) superconducting magnet. The rationally designed MgB2/SN2 cooling system was first considered by conducting a finite element analysis simulation, and then a demonstrator coil was empirically tested under the same conditions. In the SN2 cooling system design, a wide temperature distribution on the SN2 chamber was observed due to the low thermal conductivity of the stainless steel components. To overcome this temperature distribution, a copper flange was introduced to enhance the temperature uniformity of the SN2 chamber. In the coil testing, an operating current as high as 200 A was applied at 28 K (below the critical current) without any operating or thermal issues. This work was performed to further the development of SN2 cooled MgB2 superconducting coils for MRI applications. PMID:28251984

  7. Assessment of dosimetric impact of system specific geometric distortion in an MRI only based radiotherapy workflow for prostate

    Science.gov (United States)

    Gustafsson, C.; Nordström, F.; Persson, E.; Brynolfsson, J.; Olsson, L. E.

    2017-04-01

    Dosimetric errors in a magnetic resonance imaging (MRI) only radiotherapy workflow may be caused by system specific geometric distortion from MRI. The aim of this study was to evaluate the impact on planned dose distribution and delineated structures for prostate patients, originating from this distortion. A method was developed, in which computer tomography (CT) images were distorted using the MRI distortion field. The displacement map for an optimized MRI treatment planning sequence was measured using a dedicated phantom in a 3 T MRI system. To simulate the distortion aspects of a synthetic CT (electron density derived from MR images), the displacement map was applied to CT images, referred to as distorted CT images. A volumetric modulated arc prostate treatment plan was applied to the original CT and the distorted CT, creating a reference and a distorted CT dose distribution. By applying the inverse of the displacement map to the distorted CT dose distribution, a dose distribution in the same geometry as the original CT images was created. For 10 prostate cancer patients, the dose difference between the reference dose distribution and inverse distorted CT dose distribution was analyzed in isodose level bins. The mean magnitude of the geometric distortion was 1.97 mm for the radial distance of 200–250 mm from isocenter. The mean percentage dose differences for all isodose level bins, were  ⩽0.02% and the radiotherapy structure mean volume deviations were  MRI system specific distortion in a prostate MRI only radiotherapy workflow, separated from dosimetric effects originating from synthetic CT generation. No clinically relevant dose difference or structure deformation was found when 3D distortion correction and high acquisition bandwidth was used. The method could be used for any MRI sequence together with any anatomy of interest.

  8. Permanent Magnet System for MRI with Constant Gradient mechanically adjustable in Direction and Strength

    CERN Document Server

    Blümler, Peter

    2015-01-01

    A design for a permanent magnet system is proposed that generates spatially homogeneous, constant magnetic field gradients, thus creating conditions suitable for MRI without gradient coils and amplifiers. This is achieved by superimposing a weak Halbach quadrupole on a strong Halbach dipole. Rotation of either the quadrupole or the entire magnet assembly can be used to generate 2D images via filtered back-projection. Additionally, the mutual rotation of two quadrupoles can be used to scale the resulting gradient. If both gradients have identical strength the gradient can even be made to vanish. The concept is demonstrated by analytical considerations and FEM-simulations.

  9. LINEAR-DISPERSION DIVISION MULTIPLE-ACCESS FOR MIMO SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Deng Dan; Lv Xingzai; Zhu Jinkang

    2008-01-01

    Comprehensive study on novel Linear-Dispersion Division Multiple-Access (LDDMA) for multi-user uplink Multiple-Input Multiple-Output (MIMO) systems is proposed. In the new multi- plexing scheme, each user's information symbol is dispersed by a User-Specific Matrix (USM) both in space and time domain and linearly combined at base-station side. And a simple random search al- gorithm, based on capacity maximization criteria, is developed to generate a bank of USMs. Simulation results are presented to demonstrate the advantages of LDDMA. When the Bit Error Rate (BER) reaches 10, the performance gains are 3dB and 5dB, compared with Time-Division Linear Dispersion Codes (TD-LDC) and BLAST, respectively.

  10. Access to Papanicolaou Test by the Unified Health System users

    Directory of Open Access Journals (Sweden)

    Vanessa Franco de Carvalho

    2016-01-01

    Full Text Available Objective: to understand how is the access to the public health service users in the Papanicolaou Test. Methods: qualitative study, with 52 women who have changes in the Pap smear exam, questioning the exam achievement frequency and the difficulties of its access and the consultations. It was developed a thematic analysis based on the Fekete accessibility reference. Results: three categories emerged: access to information on the frequency of Pap smears, highlighting the completion of the examination linked only to the professional application; access to Pap smears, in which most women do not have difficulty; access to a return visit, showing the difficulty of women getting back into service after the exam. Conclusion: most women have easy access to the Pap smear. However, there are limitations on the return visit, hindering to establish immediate actions to the beginning of treatment.

  11. Access to Papanicolaou Test by the Unified Health System users

    Directory of Open Access Journals (Sweden)

    Vanessa Franco de Carvalho

    2016-05-01

    Full Text Available Objective: to understand how is the access to the public health service users in the Papanicolaou Test. Methods: qualitative study, with 52 women who have changes in the Pap smear exam, questioning the exam achievement frequency and the difficulties of its access and the consultations. It was developed a thematic analysis based on the Fekete accessibility reference. Results: three categories emerged: access to information on the frequency of Pap smears, highlighting the completion of the examination linked only to the professional application; access to Pap smears, in which most women do not have difficulty; access to a return visit, showing the difficulty of women getting back into service after the exam. Conclusion: most women have easy access to the Pap smear. However, there are limitations on the return visit, hindering to establish immediate actions to the beginning of treatment.

  12. Multi-Channel SQUID System for MEG and Ultra-Low-Field MRI

    CERN Document Server

    Zotev, V S; Volegov, P L; Sandin, H J; Espy, M A; Mosher, J C; Urbaitis, A V; Newman, S G; Zotev, Vadim S.; Matlachov, Andrei N.; Volegov, Petr L.; Sandin, Henrik J.; Espy, Michelle A.; Mosher, John C.; Urbaitis, Algis V.; Newman, Shaun G.; Jr, Robert H. Kraus

    2007-01-01

    A seven-channel system capable of performing both magnetoencephalography (MEG) and ultra-low-field magnetic resonance imaging (ULF MRI) is described. The system consists of seven second-order SQUID gradiometers with 37 mm diameter and 60 mm baseline, having magnetic field resolution of 1.2-2.8 fT/rtHz. It also includes four sets of coils for 2-D Fourier imaging with pre-polarization. The system's MEG performance was demonstrated by measurements of auditory evoked response. The system was also used to obtain a multi-channel 2-D image of a whole human hand at the measurement field of 46 microtesla with 3 by 3 mm resolution.

  13. Stroke patients with cerebral microbleeds on MRI scans have arteriolosclerosis as well as systemic atherosclerosis.

    Science.gov (United States)

    Shimoyama, Takashi; Iguchi, Yasuyuki; Kimura, Kazumi; Mitsumura, Hidetaka; Sengoku, Renpei; Kono, Yu; Morita, Masayo; Mochio, Soichiro

    2012-10-01

    Cerebral microbleeds (CMBs) are recognized as a manifestation of arteriolosclerosis in cerebral small vessels. However, little is known regarding whether stroke patients with CMBs often have systemic atherosclerosis. The aim of the present study was to elucidate this issue using the cardio-ankle vascular index (CAVI), a new index of systemic atherosclerosis, in acute ischemic stroke patients. We prospectively studied 105 patients (71 males, median age=70.0 years) with acute ischemic stroke. All of the patients were examined using T2*-weighted gradient echo magnetic resonance imaging (MRI) to look for and assess the CMBs and using fluid-attenuated inversion recovery to evaluate white matter hyperintensity (WMH). We assigned the patients into CMB and non-CMB groups and compared the clinical characteristics of these groups. The factors associated with CMBs were investigated using multivariate logistic regression analysis. T2*-weighted gradient echo MRI revealed CMBs in 47 patients (44.8%) and no CMBs in 58 patients (55.2%). The CAVI was significantly higher in the CMBs group (10.5 vs. 8.6, PCMBs. A high CAVI was independently associated with CMBs in patients with acute ischemic stroke. Our results indicated that ischemic stroke patients with CMBs may have cerebral arteriolosclerosis as well as systemic atherosclerosis.

  14. 78 FR 51810 - Twenty-Fourth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-08-21

    ... Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control... RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held...

  15. 78 FR 31627 - Twenty-Second Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-05-24

    ...: RTCA Special Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation... 224, Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty-second meeting of the RTCA Special Committee 224, Airport Security Access...

  16. 76 FR 50811 - Eighth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-08-16

    ... Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 224: Airport Security Access Control...

  17. 76 FR 9632 - Fifth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-02-18

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Access Control Systems (Update to DO-230B): Agenda March 10, 2011 Welcome/Introductions/Administrative... Federal Aviation Administration Fifth Meeting: RTCA Special Committee 224: Airport Security Access...

  18. LAPAROSCOPIC SALPINGECTOMY IN TWO CAPTIVE LEOPARDS (PANTHERA PARDUS) USING A SINGLE PORTAL ACCESS SYSTEM.

    Science.gov (United States)

    Hartman, Marthinus J; Monnet, Eric; Kirberger, Robert M; Schoeman, Johan P

    2015-12-01

    Laparoscopic salpingectomy was performed in two adult leopards (Panthera pardus) using a single portal access system, with a multicannulated single-incision laparoscopic surgery port, without any complications. The poorly developed ovarian bursa provided easy access to the uterine tube for salpingectomy. Laparoscopic salpingectomy can be safely performed in the leopard using a single portal access system.

  19. Relevance of MRI in prediction of malignancy of musculoskeletal system-A prospective evaluation

    Directory of Open Access Journals (Sweden)

    Wahab Shagufta

    2009-10-01

    Full Text Available Abstract Background The purpose of this study is to evaluate the role of MRI in musculoskeletal tumours, especially, in prediction of malignancy & to compare whether the diagnosis made on MRI correlates with the cytological/histopathological diagnosis. Methods 50 consecutive patients presenting in the Outpatient and Inpatient department of the Department of Orthopaedics or Casualty of Jawaharlal Nehru Medical College and Hospital, AMU, Aligarh, India were included in this study. They were subjected to MR examination on 1.5 Tesla superconducting system (MAGNETOM Avanto, Siemens. After localizer sequences, T1W and STIR images were obtained in longitudinal planes followed by T2W and post contrast T1W images in axial planes. Additional sequences were taken when required. Various imaging characteristics of tumours were evaluated statistically and their respective sensitivity and specificity in prediction of malignancy were obtained. Results Features associated with benign diagnosis in a large percentage of cases, are size less than 8 cm, sharp margination, homogeneous T2 signal, absence of oedema, necrosis, calcification and fluid-fluid levels. Similarly, malignant tumours are commonly associated with presence of irregular margins, inhomogeneous signal intensity, oedema, necrosis, haemorrhage, fascial penetration, bone changes and neurovascular involvement. A correct histological diagnosis is reached on the basis of imaging studies alone in 65% to 75% of cases. The sensitivity for a MRI diagnosis of malignant tumour was 95% and specificity was 84%. Conclusion Differentiation of malignant from benign lesions of musculoskeletal system is best made by a combination of clinical and imaging parameters rather than by any single MR characteristic. When a lesion has a non-specific MR imaging appearance, it is useful to formulate a suitably ordered differential diagnosis based on tumour prevalence, patient age, and anatomic location. A systematic approach

  20. fMRI mapping of the visual system in the mouse brain with interleaved snapshot GE-EPI.

    Science.gov (United States)

    Niranjan, Arun; Christie, Isabel N; Solomon, Samuel G; Wells, Jack A; Lythgoe, Mark F

    2016-06-10

    The use of functional magnetic resonance imaging (fMRI) in mice is increasingly prevalent, providing a means to non-invasively characterise functional abnormalities associated with genetic models of human diseases. The predominant stimulus used in task-based fMRI in the mouse is electrical stimulation of the paw. Task-based fMRI in mice using visual stimuli remains underexplored, despite visual stimuli being common in human fMRI studies. In this study, we map the mouse brain visual system with BOLD measurements at 9.4T using flashing light stimuli with medetomidine anaesthesia. BOLD responses were observed in the lateral geniculate nucleus, the superior colliculus and the primary visual area of the cortex, and were modulated by the flashing frequency, diffuse vs focussed light and stimulus context. Negative BOLD responses were measured in the visual cortex at 10Hz flashing frequency; but turned positive below 5Hz. In addition, the use of interleaved snapshot GE-EPI improved fMRI image quality without diminishing the temporal contrast-noise-ratio. Taken together, this work demonstrates a novel methodological protocol in which the mouse brain visual system can be non-invasively investigated using BOLD fMRI.

  1. A computer-aided diagnosis system for breast DCE-MRI at high spatiotemporal resolution

    NARCIS (Netherlands)

    Dalmis, M.U.; Gubern-Merida, A.; Vreemann, S.; Karssemeijer, N.; Mann, R.; Platel, B.

    2016-01-01

    PURPOSE: With novel MRI sequences, high spatiotemporal resolution has become available in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) of the breast. Since benign structures in the breast can show enhancement similar to malignancies in DCE-MRI, characterization of detected lesions

  2. Compact Wireless Access Nodes for WDM Bidirectional Radio-over-Fiber System Based on RSOA

    DEFF Research Database (Denmark)

    Yu, Xianbin; Gibbon, Timothy Braidwood; Tafur Monroy, Idelfonso

    2009-01-01

    We demonstrate a RSOA based WDM radio-over-fiber, bidirectional system for wireless access networks. The multi-functionalities of a RSOA, such as colorless operation, re-modulation and envelope detection, make wireless access nodes more compact.......We demonstrate a RSOA based WDM radio-over-fiber, bidirectional system for wireless access networks. The multi-functionalities of a RSOA, such as colorless operation, re-modulation and envelope detection, make wireless access nodes more compact....

  3. Fetal lung volume measurement by MRI with high-speed imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Osada, Hisao; Kaku, Kenshi [Chiba Univ. (Japan). Hospital

    2002-08-01

    Although ultrasonography is widely used for fetal morphologic observation, magnetic resonance imaging (MRI) has gained popularity as a new prenatal diagnostic method with recent introduction of high-speed imaging systems. Infants with lung hypoplasia affecting respiratory function require intensive management starting immediately after birth. Therefore, accurate prenatal differential diagnosis and severity evaluation are extremely important for these fetuses. The aim of this study is to measure fetal lung volume using a computer-based, three-dimensional MRI imaging system and to evaluate the possibility of clinical applications of this procedure. A total of 96 fetuses were evaluated, all were morphologically abnormal, and MRI was done for advanced assessment from 24 to 39 weeks gestation. Three-directional views of fetal chest were imaged by Signa Horizon, 1.5 Tesla, version 5.6 (General Electronics) with the following conditions; coil: TORSO coil, sequence: SSFSE (single shot fast spin echo), slice thickness: 5 mm, and imaging speed: 2 seconds/slice. To calculate the lung volume and create three-dimensional image, the lung area in each slice was traced out, then multiplied using computer image processing. Simultaneously, the volumes of all slices were summed to give the volume of each lung. Linear regression analysis and analysis of covariance (ANCOVA) were used for statistical analyses. In all cases, clear images were obtained, and were adequate for three-dimensional evaluation of the fetal lung. Thirty-five fetuses had poor outcomes, such as intrauterine fetal death, neonatal death, and intensive respiratory care. Regression lines of lung volume versus gestational week were calculated for these fetuses with poor outcome and 61 other fetuses with good outcome. ANCOVA, with gestational week as a covariant, revealed a significant intergroup difference in the lung volume (p<0.001). Similarly, regression lines of lung volume versus fetal body weight estimated by

  4. Software interface system for Geophysical Data Access and Management System (GPDAMS-CD)

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.

    -friendly access to large volume of data and means to visualize and extract selected data as per need. The software requires a minimum of computing expertise as it is controlled by a system of `pull down' menus, backed up by a context-sensitive system...

  5. Preoperative indication for systemic therapy extended to patients with early-stage breast cancer using multiparametric 7-tesla breast MRI.

    Science.gov (United States)

    Schmitz, A M T; Veldhuis, W B; Menke-Pluijmers, M B E; van der Kemp, W J M; van der Velden, T A; Viergever, M A; Mali, W P T M; Kock, M C J M; Westenend, P J; Klomp, D W J; Gilhuijs, K G A

    2017-01-01

    To establish a preoperative decision model for accurate indication of systemic therapy in early-stage breast cancer using multiparametric MRI at 7-tesla field strength. Patients eligible for breast-conserving therapy were consecutively included. Patients underwent conventional diagnostic workup and one preoperative multiparametric 7-tesla breast MRI. The postoperative (gold standard) indication for systemic therapy was established from resected tumor and lymph-node tissue, based on 10-year risk-estimates of breast cancer mortality and relapse using Adjuvant! Online. Preoperative indication was estimated using similar guidelines, but from conventional diagnostic workup. Agreement was established between preoperative and postoperative indication, and MRI-characteristics used to improve agreement. MRI-characteristics included phospomonoester/phosphodiester (PME/PDE) ratio on 31-phosphorus spectroscopy (31P-MRS), apparent diffusion coefficients on diffusion-weighted imaging, and tumor size on dynamic contrast-enhanced (DCE)-MRI. A decision model was built to estimate the postoperative indication from preoperatively available data. We included 46 women (age: 43-74yrs) with 48 invasive carcinomas. Postoperatively, 20 patients (43%) had positive, and 26 patients (57%) negative indication for systemic therapy. Using conventional workup, positive preoperative indication agreed excellently with positive postoperative indication (N = 8/8; 100%). Negative preoperative indication was correct in only 26/38 (68%) patients. However, 31P-MRS score (p = 0.030) and tumor size (p = 0.002) were associated with the postoperative indication. The decision model shows that negative indication is correct in 21/22 (96%) patients when exempting tumors larger than 2.0cm on DCE-MRI or with PME>PDE ratios at 31P-MRS. Preoperatively, positive indication for systemic therapy is highly accurate. Negative indication is highly accurate (96%) for tumors sized ≤2,0cm on DCE-MRI and with PME

  6. A system for success: BMC Systems Biology, a new open access journal

    Directory of Open Access Journals (Sweden)

    Webb Penelope A

    2007-09-01

    Full Text Available Abstract BMC Systems Biology is the first open access journal spanning the growing field of systems biology from molecules up to ecosystems. The journal has launched as more and more institutes are founded that are similarly dedicated to this new approach. BMC Systems Biology builds on the ongoing success of the BMC series, providing a venue for all sound research in the systems-level analysis of biology.

  7. Concurrent TMS-fMRI Reveals Interactions between Dorsal and Ventral Attentional Systems

    DEFF Research Database (Denmark)

    Leitao, Joana; Thielscher, Axel; Tuennerhoff, Johannes

    2015-01-01

    Adaptive behavior relies on combining bottom-up sensory inputs with top-down control signals to guide responses in line with current goals and task demands. Over the past decade, accumulating evidence has suggested that the dorsal and ventral frontoparietal attentional systems are recruited...... interactively in this process. This fMRI study used concurrent transcranial magnetic stimulation (TMS) as a causal perturbation approach to investigate the interactions between dorsal and ventral attentional systems and sensory processing areas. In a sustained spatial attention paradigm, human participants......-TMS relative to Sham-TMS increased activation in the parietal cortex regardless of sensory stimulation, confirming the neural effectiveness of TMS stimulation. Visual targets increased activations in the anterior insula, a component of the ventral attentional system responsible for salience detection...

  8. Augmented-reality visualization in iMRI operating room: system description and preclinical testing

    Science.gov (United States)

    Sauer, Frank; Khamene, Ali; Bascle, Benedicte; Vogt, Sebastian; Rubino, Gregory

    2002-05-01

    We developed an augmented reality system targeting image guidance for surgical procedures. The surgeon wears a video- see-through head mounted display that provides him with a stereo video view of the patient. The live video images are augmented with graphical representations of anatomical structures that are segmented from medical image data. The surgeon can see, e.g., a tumor in its actual location inside the patient. This in-situ visualization, where the computer maps the image information onto the patient, promises the most direct, intuitive guidance for surgical procedures. In this paper, we describe technical details of the system and its installation in UCLA's iMRI operating room. We added instrument tracking to the capabilities of our system to prepare it for minimally invasive procedures. We discuss several pre-clinical phantom experiments that support the potential clinical usefulness of augmented reality guidance.

  9. A simple scoring system for breast MRI interpretation: does it compensate for reader experience?

    Science.gov (United States)

    Marino, Maria Adele; Clauser, Paola; Woitek, Ramona; Wengert, Georg J; Kapetas, Panagiotis; Bernathova, Maria; Pinker-Domenig, Katja; Helbich, Thomas H; Preidler, Klaus; Baltzer, Pascal A T

    2016-08-01

    To investigate the impact of a scoring system (Tree) on inter-reader agreement and diagnostic performance in breast MRI reading. This IRB-approved, single-centre study included 100 patients with 121 consecutive histopathologically verified lesions (52 malignant, 68 benign). Four breast radiologists with different levels of MRI experience and blinded to histopathology retrospectively evaluated all examinations. Readers independently applied two methods to classify breast lesions: BI-RADS and Tree. BI-RADS provides a reporting lexicon that is empirically translated into likelihoods of malignancy; Tree is a scoring system that results in a diagnostic category. Readings were compared by ROC analysis and kappa statistics. Inter-reader agreement was substantial to almost perfect (kappa: 0.643-0.896) for Tree and moderate (kappa: 0.455-0.657) for BI-RADS. Diagnostic performance using Tree (AUC: 0.889-0.943) was similar to BI-RADS (AUC: 0.872-0.953). Less experienced radiologists achieved AUC: improvements up to 4.7 % using Tree (P-values: 0.042-0.698); an expert's performance did not change (P = 0.526). The least experienced reader improved in specificity using Tree (16 %, P = 0.001). No further sensitivity and specificity differences were found (P > 0.1). The Tree scoring system improves inter-reader agreement and achieves a diagnostic performance similar to that of BI-RADS. Less experienced radiologists, in particular, benefit from Tree. • The Tree scoring system shows high diagnostic accuracy in mass and non-mass lesions. • The Tree scoring system reduces inter-reader variability related to reader experience. • The Tree scoring system improves diagnostic accuracy in non-expert readers.

  10. Navy Commercial Access Control System Did Not Effectively Mitigate Access Control Risks

    Science.gov (United States)

    2013-09-16

    the capability to perform NCIC checks to vet contractor employees, and not all Navy installations nave the ability to access NCIC, NCACS is not...Management Corp 10,017 REA to contract N40085-06-D-1260 Goodwill Industries 199,148 Overhead charge to contract N00189-09- C-Z003 DynCorp international

  11. "What Page, Miss?" Enhancing Text Accessibility with DAISY (Digital Accessible Information SYstem)

    Science.gov (United States)

    Spooner, Sue

    2014-01-01

    Introduction: The provision of specially formatted materials is a complex and increasingly difficult task, given the extensive and burgeoning range of texts and resources available for classroom use. The need to extend the provision of accessible formats to include digital resources (in addition to braille, audio, and large print) led to a study…

  12. The role of CRIS systems in measuring Open Access publications

    NARCIS (Netherlands)

    Scharnhorst, A.M.; Dijk, E.M.S.; Doorn, P.K.; van Berchum, M.

    2016-01-01

    Open Access to scientific results - from publications to data - is high on the agenda of science policy drivers. Since long there is no doubt that making your own research available on the web is the best way to gain visibility and impact (Lawrence 2001). The Open Access movement started with calls

  13. Single port access surgery with a novel Port Camera system.

    Science.gov (United States)

    Terry, Benjamin S; Schoen, Jonathan; Mills, Zachary; Rentschler, Mark E

    2012-06-01

    In this work, the authors designed, built, and tested a novel port camera system for single port access (SPA) laparoscopic surgery. This SPA Port Camera device integrates the monitor, laparoscopic camera, and light source into an inexpensive, portable cannula port. The device uses a 2-channel SPA port inserted through an umbilical incision, similar to traditional SPA. After insertion into a channel, the device deploys a small camera module and LED lamp in vivo. An integrated, on-patient LCD provides the view of the surgical site. The design intent of the port camera is to enhance SPA by (a) reducing the size of the SPA port through the elimination of the dedicated laparoscope channel; (b) reducing equipment cost by integrating an inexpensive CMOS sensor and LED lamp at the port tip; (c) eliminating the need for an assistant who operates the laparoscope; and (d) mechanically coupling the camera, tool port, and on-patient LCD screen. The effectiveness of the device was evaluated by comparing the video performance with a leading industry laparoscope and by performing a user evaluation study and live porcine surgery with the device. Effectiveness of the device was mixed. Overall video system performance of the device is better than an industry standard high-definition laparoscope, implying that significant cost savings over a traditional system are possible. Participant study results suggest that simulated laparoscopic tasks are as efficient with the SPA Port Camera as they are with a typical SPA configuration. However, live surgery revealed several shortcomings of the SPA Port Camera.

  14. Quantitative MRI study of progressive cerebral atrophy in multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Konagaya, Masaaki; Matsuoka, Yukihiko [Suzuka National Hospital, Suzuka, Mie (Japan); Konagaya, Yoko [JR Tokai General Hospital, Nagoya (Japan)

    2002-02-01

    We investigated cerebral atrophy in multiple system atrophy (MSA) by quantitative analysis of MRI. The subjects were 28 patients with MSA (14 striato-nigral degeneration; SND, 14 olivo-ponto-cerebellar atrophy; OPCA. 106 MRI examinations were performed totally) and 85 normal persons for control. The ratios of the ventral pons to the infratentorial space in the sagittal section, the putamen, cerebrum, frontal lobe and parietal and occipital lobes to the intracranial space in the horizontal section, and the temporal lobe to the intracranial space in the coronal section were measured. In the early stage of the disease, OPCA showed significant atrophy of the ventral pons compared with SND, and conversely, SND demonstrated significantly smaller putamen than that in OPCA. According to the progression of the disease, the atrophy of these neural tissues progressed, which resulted in so significant differences between SND and OPCA. The cerebral atrophy was observed in 17 MSA patients. The atrophy of the frontal lobe was much frequent and prominent to that in the temporal lobe and parietal and occipital lobes. SND showed higher incidence of the cerebral atrophy than OPCA in the early stage of the disease. In long period follow-up cases, one case showed cerebral atrophy in earlier stage, and another case in late stage. We indicated the involvement of the cerebral hemispheres in MSA, especially the frontal lobe. (author)

  15. MRI screening for breast cancer in women at high risk; is the Australian breast MRI screening access program addressing the needs of women at high risk of breast cancer?

    Energy Technology Data Exchange (ETDEWEB)

    Schenberg, Tess [Department of Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Familial Cancer Centre, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Mitchell, Gillian [Familial Cancer Centre, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia); Taylor, Donna [School of Surgery, University of Western Australia, Perth, Western Australia (Australia); Department of Radiology, Royal Perth Hospital, Perth, Western Australia (Australia); BreastScreen Western Australia, Adelaide Terrace, Perth, Western Australia (Australia); Saunders, Christobel [School of Surgery, University of Western Australia, Perth, Western Australia (Australia); Department of General Surgery, St John of God Hospital, Perth, Western Australia (Australia); Department of Medical Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria (Australia)

    2015-09-15

    Breast magnetic resonance imaging (MRI) screening of women under 50 years old at high familial risk of breast cancer was given interim funding by Medicare in 2009 on the basis that a review would be undertaken. An updated literature review has been undertaken by the Medical Services Advisory Committee but there has been no assessment of the quality of the screening or other screening outcomes. This review examines the evidence basis of breast MRI screening and how this fits within an Australian context with the purpose of informing future modifications to the provision of Medicare-funded breast MRI screening in Australia. Issues discussed will include selection of high-risk women, the options for MRI screening frequency and measuring the outcomes of screening.

  16. An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification.

    Directory of Open Access Journals (Sweden)

    Muhammad Faisal Siddiqui

    Full Text Available A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT, principal component analysis (PCA, and least squares support vector machine (LS-SVM are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%. Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities

  17. An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification.

    Science.gov (United States)

    Siddiqui, Muhammad Faisal; Reza, Ahmed Wasif; Kanesan, Jeevan

    2015-01-01

    A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI) as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT), principal component analysis (PCA), and least squares support vector machine (LS-SVM) are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF) kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%). Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities from the

  18. Chest MRI

    Science.gov (United States)

    Nuclear magnetic resonance - chest; Magnetic resonance imaging - chest; NMR - chest; MRI of the thorax; Thoracic MRI ... healthy enough to filter the contrast. During the MRI, the person who operates the machine will watch ...

  19. A computer-aided detection system for rheumatoid arthritis MRI data interpretation and quantification of synovial activity

    DEFF Research Database (Denmark)

    Kubassove, Olga; Boesen, Mikael; Cimmino, Marco A;

    2009-01-01

    RATIONAL AND OBJECTIVE: Disease assessment and follow-up of rheumatoid arthritis (RA) patients require objective evaluation and quantification. Magnetic resonance imaging (MRI) has a large potential to supplement such information for the clinician, however, time spent on data reading...... and interpretation slow down development in this area. Existing scoring systems of especially synovitis are too rigid and insensitive to measure early treatment response and quantify inflammation. This study tested a novel automated, computer system for analysis of dynamic MRI data acquired from patients with RA...

  20. Tinamit: Making coupled system dynamics models accessible to stakeholders

    Science.gov (United States)

    Malard, Julien; Inam Baig, Azhar; Rojas Díaz, Marcela; Hassanzadeh, Elmira; Adamowski, Jan; Tuy, Héctor; Melgar-Quiñonez, Hugo

    2017-04-01

    Model coupling is increasingly used as a method of combining the best of two models when representing socio-environmental systems, though barriers to successful model adoption by stakeholders are particularly present with the use of coupled models, due to their high complexity and typically low implementation flexibility. Coupled system dynamics - physically-based modelling is a promising method to improve stakeholder participation in environmental modelling while retaining a high level of complexity for physical process representation, as the system dynamics components are readily understandable and can be built by stakeholders themselves. However, this method is not without limitations in practice, including 1) inflexible and complicated coupling methods, 2) difficult model maintenance after the end of the project, and 3) a wide variety of end-user cultures and languages. We have developed the open-source Python-language software tool Tinamit to overcome some of these limitations to the adoption of stakeholder-based coupled system dynamics - physically-based modelling. The software is unique in 1) its inclusion of both a graphical user interface (GUI) and a library of available commands (API) that allow users with little or no coding abilities to rapidly, effectively, and flexibly couple models, 2) its multilingual support for the GUI, allowing users to couple models in their preferred language (and to add new languages as necessary for their community work), and 3) its modular structure allowing for very easy model coupling and modification without the direct use of code, and to which programming-savvy users can easily add support for new types of physically-based models. We discuss how the use of Tinamit for model coupling can greatly increase the accessibility of coupled models to stakeholders, using an example of a stakeholder-built system dynamics model of soil salinity issues in Pakistan coupled with the physically-based soil salinity and water flow model

  1. A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems.

    Science.gov (United States)

    Choi, Donghee; Kim, Dohoon; Park, Seog

    2015-01-01

    Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment.

  2. Database Security System for Applying Sophisticated Access Control via Database Firewall Server

    OpenAIRE

    Eun-Ae Cho; Chang-Joo Moon; Dae-Ha Park; Kang-Bin Yim

    2014-01-01

    Database security, privacy, access control, database firewall, data break masking Recently, information leakage incidents have occurred due to database security vulnerabilities. The administrators in the traditional database access control methods grant simple permissions to users for accessing database objects. Even though they tried to apply more strict permissions in recent database systems, it was difficult to properly adopt sophisticated access control policies to commercial databases...

  3. Evaluating accessibility to Bangkok Metro Systems using multi-dimensional criteria across user groups

    OpenAIRE

    Duangporn Prasertsubpakij; Vilas Nitivattananon

    2012-01-01

    Metro systems act as fast and efficient transport systems for many modern metropolises; however, enhancing higher usage of such systems often conflicts with providing suitable accessibility options. The traditional approach of metro accessibility studies seems to be an ineffective measure to gage sustainable access in which the equal rights of all users are taken into account. Bangkok Metropolitan Region (BMR) transportation has increasingly relied on the role of two mass rapid transport syst...

  4. An Efficient Role and Object Based Access Control Model Implemented in a PDM System

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiaowen; TAN Jian; HUANG Xiangguo

    2006-01-01

    An effective and reliable access control is crucial to a PDM system. This article has discussed the commonly used access control models, analyzed their advantages and disadvantages, and proposed a new Role and Object based access control model that suits the particular needs of a PDM system. The new model has been implemented in a commercial PDM system, which has demonstrated enhanced flexibility and convenience.

  5. Task-role-based Access Control Model in Smart Health-care System

    Directory of Open Access Journals (Sweden)

    Wang Peng

    2015-01-01

    Full Text Available As the development of computer science and smart health-care technology, there is a trend for patients to enjoy medical care at home. Taking enormous users in the Smart Health-care System into consideration, access control is an important issue. Traditional access control models, discretionary access control, mandatory access control, and role-based access control, do not properly reflect the characteristics of Smart Health-care System. This paper proposes an advanced access control model for the medical health-care environment, task-role-based access control model, which overcomes the disadvantages of traditional access control models. The task-role-based access control (T-RBAC model introduces a task concept, dividing tasks into four categories. It also supports supervision role hierarchy. T-RBAC is a proper access control model for Smart Health-care System, and it improves the management of access rights. This paper also proposes an implementation of T-RBAC, a binary two-key-lock pair access control scheme using prime factorization.

  6. From System Expansion to System Contraction: Access to Higher Education in Poland

    Science.gov (United States)

    Kwiek, Marek

    2013-01-01

    Access to higher education in Poland is changing due to the demography of smaller cohorts of potential students. Following a demand-driven educational expansion after the collapse of communism in 1989, the higher education system is now contracting. Such expansion/contraction and growth/decline in European higher education has rarely been…

  7. Presidential Management Fellows (PMF) Talent Acquisition System, PMF-TAS (ACCESS CONTROLLED)

    Data.gov (United States)

    Office of Personnel Management — Application and Assessment system for Presidential Management Fellows (PMF) and PMF Science, Technology, Engineering, and Math (STEM) programs. This sytem is access...

  8. 78 FR 16757 - Twentieth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-03-18

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held April 4, 2013 from...

  9. 78 FR 43963 - Twenty-Third Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-07-22

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held on June 20,...

  10. 77 FR 71474 - Seventeenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-11-30

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held December 13,...

  11. 77 FR 15448 - Twelfth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-03-15

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of meeting RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... 224, Airport Security Access Control Systems DATES: The meeting will be held April 5, 2012, from 10...

  12. 78 FR 22025 - Twenty First Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-04-12

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held April 9-10,...

  13. 77 FR 55894 - Fifteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-09-11

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems DATES: The meeting will be held September 27-28,...

  14. 76 FR 38742 - Seventh Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-07-01

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held July 15, 2011, from 10 a.m. to 1 p.m....

  15. 77 FR 64838 - Sixteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-10-23

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held November 15,...

  16. 78 FR 7850 - Nineteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-02-04

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held February 21,...

  17. 76 FR 3931 - Fourth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-01-21

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 Meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held February 8, 2011, from 10 a.m. to 5...

  18. 75 FR 71790 - Second Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-11-24

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held December 9, 2010, from 10 a.m. to 5...

  19. 77 FR 2343 - Eleventh Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-01-17

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY: The FAA..., Airport Security Access Control Systems. DATES: The meeting will be held February 9, 2012, from 10...

  20. 48 CFR 504.602-71 - Federal Procurement Data System-Public access to data.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Federal Procurement Data System-Public access to data. 504.602-71 Section 504.602-71 Federal Acquisition Regulations System... Procurement Data System—Public access to data. (a) The FPDS database. The General Services...

  1. Efficiency of unenhanced MRI in the diagnosis of acute appendicitis: Comparison with Alvarado scoring system and histopathological results

    Energy Technology Data Exchange (ETDEWEB)

    Inci, Ercan, E-mail: ercan_inci@mynet.com [Department of Radiology, Istanbul Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Incirli-Bakirkoy, Istanbul (Turkey); Hocaoglu, Elif; Aydin, Sibel; Palabiyik, Figen; Cimilli, Tan [Department of Radiology, Istanbul Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Incirli-Bakirkoy, Istanbul (Turkey); Turhan, Ahmet Nuray; Ayguen, Ersan [Department of Surgery, Istanbul Bakirkoy Dr. Sadi Konuk Training and Research Hospital, Istanbul (Turkey)

    2011-11-15

    Purpose: The purpose of this study was to assess the diagnostic value of unenhanced magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis and compare with Alvarado scores and histopathological results. Materials and methods: The study included 85 consecutive patients (mean age, 26.5 {+-} 11.3 years) who were clinically suspected of having acute appendicitis. Each patients Alvarado scores were recorded and unenhanced MRI was performed, consisting of T1-weighted, T2-weighted and fat-suppressed T2-weighted fast spin-echo sequences. The MR images were prospectively reviewed in consensus for the presence of acute appendicitis by two radiologists who were blinded to the results of the Alvarado scores. The study population were divided into three subgroups based on the MRI findings: Group I: definitely not appendicitis, Group II: probably appendicitis, Group III: definitely appendicitis. All patients were divided into two subgroups according to Alvarado scores as Group A (low: 1-6), and Group B (high: 7-10). MR findings were compared with Alvarado scores and histopathological findings. Results: Sixty-six (77.6%) of the 85 patients with clinically suspected acute appendicitis, had undergone surgery. The diagnosis of appendicitis could be correctly achieved with MRI in 55 (83.3%) of 57 (86.4%) patients with histopathologically proven acute appendicitis. The sensitivity, specificity, positive predictive value and negative predictive value of MRI examination and Alvarado scoring system in the diagnosis of acute appendicitis were 96.49%, 66.67%, 94.83%, 75.0% and 84.21%, 66.67%, 94.12%, 40.0%, respectively. Conclusions: MRI is a valuable technique for detecting acute appendicitis even in the cases with low Alvarado scores. To increase the diagnostic accuracy and preventing unnecessary laparotomies for suspected appendicitis, shorter and cheaper unenhanced basic MRI may be performed.

  2. MRI in psychiatry

    Energy Technology Data Exchange (ETDEWEB)

    Mulert, Christoph [UKE, Hamburg (Germany). Psychiatry Neuroimaging Branch; Shenton, Martha E. (ed.) [Harvard Medical School, Boston, MA (United States). Dept. of Psychiatry and Radiology

    2014-07-01

    This is the first comprehensive textbook on the use of MRI in psychiatry covering imaging techniques, brain systems and a review of findings in different psychiatric disorders. The book is divided into three sections, the first of which covers in detail all the major MRI-based methodological approaches available today, including fMRI, EEG-fMRI, DTI, and MR spectroscopy. In addition, the role of MRI in imaging genetics and combined brain stimulation and imaging is carefully explained. The second section provides an overview of the different brain systems that are relevant for psychiatric disorders, including the systems for perception, emotion, cognition, and reward. The final part of the book presents the MRI findings that are obtained in all the major psychiatric disorders using the previously discussed techniques. Numerous carefully chosen images support the informative text, making this an ideal reference work for all practitioners and trainees with an interest in this flourishing field.

  3. MRI and low back pain

    Science.gov (United States)

    Backache - MRI; Low back pain - MRI; Lumbar pain - MRI; Back strain - MRI; Lumbar radiculopathy - MRI; Herniated intervertebral disk - MRI; Prolapsed intervertebral disk - MRI; Slipped disk - MRI; Ruptured ...

  4. A multimodal MRI approach to identify and characterize microstructural brain changes in neuropsychiatric systemic lupus erythematosus

    Science.gov (United States)

    Ercan, Ece; Ingo, Carson; Tritanon, Oranan; Magro-Checa, Cesar; Smith, Alex; Smith, Seth; Huizinga, Tom; van Buchem, Mark A.; Ronen, Itamar

    2015-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease with multi-organ involvement and results in neurological and psychiatric (NP) symptoms in up to 40% of the patients. To date, the diagnosis of neuropsychiatric systemic lupus erythematosus (NPSLE) poses a challenge due to the lack of neuroradiological gold standards. In this study, we aimed to better localize and characterize normal appearing white matter (NAWM) changes in NPSLE by combining data from two quantitative MRI techniques, diffusion tensor imaging (DTI) and magnetization transfer imaging (MTI). 9 active NPSLE patients (37 ± 13 years, all females), 9 SLE patients without NP symptoms (44 ± 11 years, all females), and 14 healthy controls (HC) (40 ± 9 years, all females) were included in the study. MTI, DTI and fluid attenuated inversion recovery (FLAIR) images were collected from all subjects on a 3 T MRI scanner. Magnetization transfer ratio (MTR), mean diffusivity (MD), fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD) maps and white matter lesion maps based on the FLAIR images were created for each subject. MTR and DTI data were then co-analyzed using tract-based spatial statistics and a cumulative lesion map to exclude lesions. Significantly lower MTR and FA and significantly higher AD, RD and MD were found in NPSLE compared to HC in NAWM regions. The differences in DTI measures and in MTR, however, were only moderately co-localized. Additionally, significant differences in DTI measures, but not in MTR, were found between NPSLE and SLE patients, suggesting that the underlying microstructural changes detected by MD are linked to the onset of NPSLE. The co-analysis of the anatomical distribution of MTI and DTI measures can potentially improve the diagnosis of NPSLE and contribute to the understanding of the underlying microstructural damage. PMID:26106559

  5. A multimodal MRI approach to identify and characterize microstructural brain changes in neuropsychiatric systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Ece Ercan

    2015-01-01

    Full Text Available Systemic lupus erythematosus (SLE is an autoimmune disease with multi-organ involvement and results in neurological and psychiatric (NP symptoms in up to 40% of the patients. To date, the diagnosis of neuropsychiatric systemic lupus erythematosus (NPSLE poses a challenge due to the lack of neuroradiological gold standards. In this study, we aimed to better localize and characterize normal appearing white matter (NAWM changes in NPSLE by combining data from two quantitative MRI techniques, diffusion tensor imaging (DTI and magnetization transfer imaging (MTI. 9 active NPSLE patients (37 ± 13 years, all females, 9 SLE patients without NP symptoms (44 ± 11 years, all females, and 14 healthy controls (HC (40 ± 9 years, all females were included in the study. MTI, DTI and fluid attenuated inversion recovery (FLAIR images were collected from all subjects on a 3 T MRI scanner. Magnetization transfer ratio (MTR, mean diffusivity (MD, fractional anisotropy (FA, radial diffusivity (RD, axial diffusivity (AD maps and white matter lesion maps based on the FLAIR images were created for each subject. MTR and DTI data were then co-analyzed using tract-based spatial statistics and a cumulative lesion map to exclude lesions. Significantly lower MTR and FA and significantly higher AD, RD and MD were found in NPSLE compared to HC in NAWM regions. The differences in DTI measures and in MTR, however, were only moderately co-localized. Additionally, significant differences in DTI measures, but not in MTR, were found between NPSLE and SLE patients, suggesting that the underlying microstructural changes detected by MD are linked to the onset of NPSLE. The co-analysis of the anatomical distribution of MTI and DTI measures can potentially improve the diagnosis of NPSLE and contribute to the understanding of the underlying microstructural damage.

  6. A new MRI grading system for cervical foraminal stenosis based on axial T2-weighted images

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Su Jin; Lee, Joon Woo; Seo, Ji Woon; Kang, Heung Sik [Dept. of Radiology, , Seoul National University Bundang Hospital, Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center, Seongnam (Korea, Republic of); Chai, Jee Won [Dept. of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); Yoo, Hye Jin; Kang, Yu Suhn [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Ahn, Joong Mo [Dept. of Radiology, University of Pittsburgh Medical Center, Pittsburgh (United States)

    2015-12-15

    The purpose of this study was to evaluate the reliability of a new magnetic resonance imaging (MRI) grading system for cervical neural foraminal stenosis (NFS). Cervical NFS at bilateral C4/5, C5/6, and C6/7 was classified into the following three grades based on the T2-weighted axial images: Grade 0 = absence of NFS, with the narrowest width of the neural foramen greater than the width of the extraforaminal nerve root (EFNR); Grade 1 = the narrowest width of the neural foramen the same or less than (but more than 50% of) the width of the EFNR; Grade 2 = the width of the neural foramen the same or less than 50% of the width of the EFNR. The MRIs of 96 patients who were over 60 years old (M:F = 50:46; mean age 68.4 years; range 61-86 years) were independently analyzed by seven radiologists. Interobserver and intraobserver agreements were analyzed using the percentage agreement, kappa statistics, and intraclass correlation coefficient (ICC). For the distinction among the three individual grades at all six neural foramina, the ICC ranged from 0.68 to 0.73, indicating fair to good reproducibility. The percentage agreement ranged from 60.2% to 70.6%, and the kappa values (κ = 0.50-0.58) indicated fair to moderate agreement. The percentages of intraobserver agreement ranged from 85.4% to 93.8% (κ = 0.80-0.92), indicating near perfect agreement. The new MRI grading system shows sufficient interobserver and intraobserver agreement to reliably assess cervical NFS.

  7. Simultaneous fMRI-PET of the opioidergic pain system in human brain

    DEFF Research Database (Denmark)

    Wey, Hsiao-Ying; Catana, Ciprian; Hooker, Jacob M

    2014-01-01

    MRI and PET provide complementary information for studying brain function. While the potential use of simultaneous MRI/PET for clinical diagnostic and disease staging has been demonstrated recently; the biological relevance of concurrent functional MRI-PET brain imaging to dissect neurochemically...... in this region. Simultaneous fMRI-PET provides unique opportunities allowing us to relate specific neurochemical events to functional hemodynamic activation and to investigate the impacts of neurotransmission on neurovascular coupling of the human brain in vivo.......MRI and PET provide complementary information for studying brain function. While the potential use of simultaneous MRI/PET for clinical diagnostic and disease staging has been demonstrated recently; the biological relevance of concurrent functional MRI-PET brain imaging to dissect neurochemically...... data were acquired with an opioid radioligand, [(11)C]diprenorphine, to detect endogenous opioid releases in response to pain. BOLD fMRI data were collected at the same time to capture hemodynamic responses. In this simultaneous human fMRI-PET imaging study, we show co-localized responses in thalamus...

  8. Ultra-sensitive molecular MRI of cerebrovascular cell activation enables early detection of chronic central nervous system disorders.

    Science.gov (United States)

    Montagne, Axel; Gauberti, Maxime; Macrez, Richard; Jullienne, Amandine; Briens, Aurélien; Raynaud, Jean-Sébastien; Louin, Gaelle; Buisson, Alain; Haelewyn, Benoit; Docagne, Fabian; Defer, Gilles; Vivien, Denis; Maubert, Eric

    2012-11-01

    Since endothelial cells can be targeted by large contrast-carrying particles, molecular imaging of cerebrovascular cell activation is highly promising to evaluate the underlying inflammation of the central nervous system (CNS). In this study, we aimed to demonstrate that molecular magnetic resonance imaging (MRI) of cerebrovascular cell activation can reveal CNS disorders in the absence of visible lesions and symptoms. To this aim, we optimized contrast carrying particles targeting vascular cell adhesion molecule-1 and MRI protocols through both in vitro and in vivo experiments. Although, pre-contrast MRI images failed to reveal the ongoing pathology, contrast-enhanced MRI revealed hypoperfusion-triggered CNS injury in vascular dementia, unmasked amyloid-induced cerebrovascular activation in Alzheimer's disease and allowed monitoring of disease activity during experimental autoimmune encephalomyelitis. Moreover, contrast-enhanced MRI revealed the cerebrovascular cell activation associated with known risk factors of CNS disorders such as peripheral inflammation, ethanol consumption, hyperglycemia and aging. By providing a dramatically higher sensitivity than previously reported methods and molecular contrast agents, the technology described in the present study opens new avenues of investigation in the field of neuroinflammation.

  9. H-RBAC: A Hierarchical Access Control Model for SaaS Systems

    Directory of Open Access Journals (Sweden)

    Dancheng Li

    2011-08-01

    Full Text Available SaaS is a new way to deploy software as a hosted service and accessed over the Internet which means the customers don’t need to maintain the software code and data on their own servers. So it’s more important for SaaS systems to take security issues into account. Access control is a security mechanism that enables an authority to access to certain restricted areas and resources according to the permissions assigned to a user. Several access models have been proposed to realize the access control of single instance systems. However, most of the existing models couldn’t address the following SaaS system problems: (1 role name conflicts (2 cross-level management (3 the isomerism of tenants' access control (4 temporal delegation constraints. This paper describes a hierarchical RBAC model called H-RBAC solves all the four problems of SaaS systems mentioned above. This model addresses the SaaS system access control in both system level and tenant level. It combines the advantages of RBDM and ARBAC97 model and introduces temporal constraints to SaaS access control model. In addition, a practical approach to implement the access control module for SaaS systems based on H-RBAC model is also proposed in this paper.

  10. Testing an OMERACT MRI scoring system for peripheral psoriatic arthritis in cross-sectional and longitudinal settings

    DEFF Research Database (Denmark)

    McQueen, Fiona; Lassere, Marissa; Duer-Jensen, Anne

    2009-01-01

    OBJECTIVE: Magnetic resonance imaging (MRI) is increasingly used to measure articular inflammation and damage in patients with psoriatic arthritis (PsA). We evaluated the reliability of a new OMERACT PsA MRI scoring system, PsAMRIS, in PsA fingers. METHODS: In 2 separate studies, MRI scans were...... obtained from patients with clinical evidence of synovitis or dactylitis of the fingers. For the first cross-sectional study, images were obtained at one timepoint. For the second longitudinal study, images were obtained at 2 timepoints, 6 weeks apart. Scans were scored using PsAMRIS in an international......, reliability for change scores was acceptable only for synovitis and tenosynovitis. CONCLUSION: Further development and testing of the PsAMRIS is planned to improve its performance as a clinical and research tool to identify and measure pathology in peripheral joint PsA....

  11. Evaluating accessibility to Bangkok Metro Systems using multi-dimensional criteria across user groups

    Directory of Open Access Journals (Sweden)

    Duangporn Prasertsubpakij

    2012-07-01

    Full Text Available Metro systems act as fast and efficient transport systems for many modern metropolises; however, enhancing higher usage of such systems often conflicts with providing suitable accessibility options. The traditional approach of metro accessibility studies seems to be an ineffective measure to gage sustainable access in which the equal rights of all users are taken into account. Bangkok Metropolitan Region (BMR transportation has increasingly relied on the role of two mass rapid transport systems publicly called “BTS Skytrain” and “MRT Subway”, due to limited availability of land and massive road congestion; however, access to such transit arguably treats some vulnerable groups, especially women, the elderly and disabled people unfairly. This study constructs a multi-dimensional assessment of accessibility considerations to scrutinize how user groups access metro services based on BMR empirical case. 600 individual passengers at various stations were asked to rate the questionnaire that simultaneously considers accessibility aspects of spatial, feeder connectivity, temporal, comfort/safety, psychosocial and other dimensions. It was interestingly found by user disaggregated accessibility model that the lower the accessibility perceptions—related uncomfortable and unsafe environment conditions, the greater the equitable access to services, as illustrated by MRT — Hua Lumphong and MRT — Petchaburi stations. The study suggests that, to balance the access priorities of groups on services, policy actions should emphasize acceptably safe access for individuals, cost efficient feeder services connecting the metro lines, socioeconomic influences and time allocation. Insightful discussions on integrated approach balancing different dimensions of accessibility and recommendations would contribute to accessibility-based knowledge and potential propensity to use the public transits towards transport sustainability.

  12. Safety of magnetic resonance imaging of patients with a new Medtronic EnRhythm MRI SureScan pacing system: clinical study design

    Directory of Open Access Journals (Sweden)

    Jenniskens Inge

    2008-12-01

    Full Text Available Abstract Background Magnetic Resonance Imaging (MRI of patients with implanted cardiac devices is currently considered hazardous due to potential for electromagnetic interference to the patient and pacemaker system. With approximately 60 million MRI scans performed worldwide per year, an estimated majority of pacemaker patients may develop an indication for an MRI during the lifetime of their pacemakers, suggesting that safe use of pacemakers in the MRI environment would be clinically valuable. A new pacing system (Medtronic EnRhythm MRI™ SureScan™ and CapSureFix MRI™ leads has been designed and pre-clinically tested for safe use in the MRI environment. The EnRhythm MRI study is designed to confirm the safety and efficacy of this new pacing system. Methods The EnRhythm MRI study is a prospective, randomized controlled, unblinded clinical trial to confirm the safety and efficacy of MRI at 1.5 Tesla in patients implanted with a specifically designed pacemaker and lead system. The patients have standard indications for dual chamber pacemaker implantation. Successfully implanted patients are randomized in a 2:1 ratio to undergo MRI (MRI group or to have no MRI scan (control group at 9–12 weeks after pacemaker system implantation. Magnetic resonance (MR scanning includes 14 head and lumbar scan sequences representing clinically relevant scans while maximizing the gradient slew rate up to 200 T/m/s, and/or the transmitted radiofrequency (RF power up to SAR (specific absorption rate levels of 2 W/kg body weight (upper limit of normal operating mode. Full interrogation of all device information and sensing and capture function are measured at device implantation, every follow-up and before and immediately after MRI in the MRI group and at the same time points in the control group. Complete pacemaker and lead evaluations are also done at one week and one month after the scan for the MRI and control group patients. The primary endpoint is safe and

  13. Safety of magnetic resonance imaging of patients with a new Medtronic EnRhythm MRI SureScan pacing system: clinical study design

    Science.gov (United States)

    Sutton, Richard; Kanal, Emanuel; Wilkoff, Bruce L; Bello, David; Luechinger, Roger; Jenniskens, Inge; Hull, Michael; Sommer, Torsten

    2008-01-01

    Background Magnetic Resonance Imaging (MRI) of patients with implanted cardiac devices is currently considered hazardous due to potential for electromagnetic interference to the patient and pacemaker system. With approximately 60 million MRI scans performed worldwide per year, an estimated majority of pacemaker patients may develop an indication for an MRI during the lifetime of their pacemakers, suggesting that safe use of pacemakers in the MRI environment would be clinically valuable. A new pacing system (Medtronic EnRhythm MRI™ SureScan™ and CapSureFix MRI™ leads) has been designed and pre-clinically tested for safe use in the MRI environment. The EnRhythm MRI study is designed to confirm the safety and efficacy of this new pacing system. Methods The EnRhythm MRI study is a prospective, randomized controlled, unblinded clinical trial to confirm the safety and efficacy of MRI at 1.5 Tesla in patients implanted with a specifically designed pacemaker and lead system. The patients have standard indications for dual chamber pacemaker implantation. Successfully implanted patients are randomized in a 2:1 ratio to undergo MRI (MRI group) or to have no MRI scan (control group) at 9–12 weeks after pacemaker system implantation. Magnetic resonance (MR) scanning includes 14 head and lumbar scan sequences representing clinically relevant scans while maximizing the gradient slew rate up to 200 T/m/s, and/or the transmitted radiofrequency (RF) power up to SAR (specific absorption rate) levels of 2 W/kg body weight (upper limit of normal operating mode). Full interrogation of all device information and sensing and capture function are measured at device implantation, every follow-up and before and immediately after MRI in the MRI group and at the same time points in the control group. Complete pacemaker and lead evaluations are also done at one week and one month after the scan for the MRI and control group patients. The primary endpoint is safe and successful

  14. 76 FR 59481 - Ninth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-09-26

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 224: Airport Security Access Control...

  15. 75 FR 47464 - Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control...

    Science.gov (United States)

    2010-08-06

    ... circumvention of copyright protection systems for access control technologies which was published July 27, 2010... Copyright Office 37 CFR Part 201 Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control Technologies AGENCY: Copyright Office, Library of Congress. ACTION: Final...

  16. 75 FR 61819 - First Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-10-06

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): November 2, 2010 Welcome/Introductions/Administrative Remarks Agenda... Federal Aviation Administration First Meeting: RTCA Special Committee 224: Airport Security Access...

  17. 76 FR 16470 - Sixth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-03-23

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): Agenda April 13, 2011 Welcome/Introductions/Administrative Remarks... Federal Aviation Administration Sixth Meeting: RTCA Special Committee 224: Airport Security Access...

  18. 75 FR 80886 - Third Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-12-23

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): Agenda January 13, 2011 Welcome/Introductions/Administrative Remarks... Federal Aviation Administration Third Meeting: RTCA Special Committee 224: Airport Security Access...

  19. Upper bound for energy efficiency in multi-cell fibre-wireless access systems

    DEFF Research Database (Denmark)

    Koonen, A.M.J.; Popov, M.; Wessing, Henrik

    2013-01-01

    Bringing radio access points closer to the end-users improves radio energy efficiency. However, taking into account both the radio and the optical parts of a fibre-wireless access system, the overall system energy efficiency has an upper bound determined by the relation between the energy...

  20. Upper Bound for Energy Efficiency in Multi-Cell Fibre-Wireless Access Systems

    DEFF Research Database (Denmark)

    Koonen, A. M. J.; Popov, M.; Wessing, Henrik

    Bringing radio access points closer to the end-users improves radio energy efficiency. However, taking into account both the radio and the optical parts of a fibre-wireless access system, the overall system energy efficiency has an upper bound determined by the relation between the energy...

  1. An fMRI-compatible force measurement system for the evaluation of the neural correlates of step initiation.

    Science.gov (United States)

    de Lima-Pardini, Andrea Cristina; de Azevedo Neto, Raymundo Machado; Coelho, Daniel Boari; Boffino, Catarina Costa; Shergill, Sukhwinder S; de Oliveira Souza, Carolina; Brant, Rachael; Barbosa, Egberto Reis; Cardoso, Ellison Fernando; Teixeira, Luis Augusto; Cohen, Rajal G; Horak, Fay Bahling; Amaro, Edson

    2017-02-23

    Knowledge of brain correlates of postural control is limited by the technical difficulties in performing controlled experiments with currently available neuroimaging methods. Here we present a system that allows the measurement of anticipatory postural adjustment of human legs to be synchronized with the acquisition of functional magnetic resonance imaging data. The device is composed of Magnetic Resonance Imaging (MRI) compatible force sensors able to measure the level of force applied by both feet. We tested the device in a group of healthy young subjects and a group of elderly subjects with Parkinson's disease using an event-related functional MRI (fMRI) experiment design. In both groups the postural behavior inside the magnetic resonance was correlated to the behavior during gait initiation outside the scanner. The system did not produce noticeable imaging artifacts in the data. Healthy young people showed brain activation patterns coherent with movement planning. Parkinson's disease patients demonstrated an altered pattern of activation within the motor circuitry. We concluded that this force measurement system is able to index both normal and abnormal preparation for gait initiation within an fMRI experiment.

  2. An fMRI-compatible force measurement system for the evaluation of the neural correlates of step initiation

    Science.gov (United States)

    de Lima-Pardini, Andrea Cristina; de Azevedo Neto, Raymundo Machado; Coelho, Daniel Boari; Boffino, Catarina Costa; Shergill, Sukhwinder S.; de Oliveira Souza, Carolina; Brant, Rachael; Barbosa, Egberto Reis; Cardoso, Ellison Fernando; Teixeira, Luis Augusto; Cohen, Rajal G.; Horak, Fay Bahling; Amaro, Edson

    2017-01-01

    Knowledge of brain correlates of postural control is limited by the technical difficulties in performing controlled experiments with currently available neuroimaging methods. Here we present a system that allows the measurement of anticipatory postural adjustment of human legs to be synchronized with the acquisition of functional magnetic resonance imaging data. The device is composed of Magnetic Resonance Imaging (MRI) compatible force sensors able to measure the level of force applied by both feet. We tested the device in a group of healthy young subjects and a group of elderly subjects with Parkinson’s disease using an event-related functional MRI (fMRI) experiment design. In both groups the postural behavior inside the magnetic resonance was correlated to the behavior during gait initiation outside the scanner. The system did not produce noticeable imaging artifacts in the data. Healthy young people showed brain activation patterns coherent with movement planning. Parkinson’s disease patients demonstrated an altered pattern of activation within the motor circuitry. We concluded that this force measurement system is able to index both normal and abnormal preparation for gait initiation within an fMRI experiment. PMID:28230070

  3. Fine-Grained Access Control for Electronic Health Record Systems

    Science.gov (United States)

    Hue, Pham Thi Bach; Wohlgemuth, Sven; Echizen, Isao; Thuy, Dong Thi Bich; Thuc, Nguyen Dinh

    There needs to be a strategy for securing the privacy of patients when exchanging health records between various entities over the Internet. Despite the fact that health care providers such as Google Health and Microsoft Corp.'s Health Vault comply with the U.S Health Insurance Portability and Accountability Act (HIPAA), the privacy of patients is still at risk. Several encryption schemes and access control mechanisms have been suggested to protect the disclosure of a patient's health record especially from unauthorized entities. However, by implementing these approaches, data owners are not capable of controlling and protecting the disclosure of the individual sensitive attributes of their health records. This raises the need to adopt a secure mechanism to protect personal information against unauthorized disclosure. Therefore, we propose a new Fine-grained Access Control (FGAC) mechanism that is based on subkeys, which would allow a data owner to further control the access to his data at the column-level. We also propose a new mechanism to efficiently reduce the number of keys maintained by a data owner in cases when the users have different access privileges to different columns of the data being shared.

  4. Characterization of accessibility for affine connection control systems at some points with nonzero velocity

    CERN Document Server

    Barbero-Liñán, María

    2011-01-01

    Affine connection control systems are mechanical control systems that model a wide range of real systems such as robotic legs, hovercrafts, planar rigid bodies, rolling pennies, snakeboards and so on. In 1997 the accessibility and a particular notion of controllability was intrinsically described by A. D. Lewis and R. Murray at points of zero velocity. Here, we present a novel generalization of the description of accessibility algebra for those systems at some points with nonzero velocity as long as the affine connection restricts to the distribution given by the symmetric closure. The results are used to describe the accessibility algebra of different mechanical control systems.

  5. GENERAL APPROACHES TO OPEN ACCESS ELECTRONIC SYSTEMS USING IN SCIENTIFIC AND PEDAGOGICAL RESEARCHES

    Directory of Open Access Journals (Sweden)

    Tetiana L. Novytska

    2016-01-01

    Full Text Available In the article the electronic open access systems, which include digital libraries, electronic tables and analytical systems are considered. There is investigated the functionality of electronic systems of open access. Based on the analysis of scientific and educational research it is highlighted the main approaches to the use of digital library and general approaches to the use of electronic systems of open access. The types of searches that can be used by users of electronic libraries are investigated. There are presented the examples of scientometric and analytical systems as well as the main advantages of Google Scholar.

  6. Comparative Evaluation of Diagnostic Value of Prenatal USG and MRI in the Diagnosis of Fetal Central Nervous System Defects

    Directory of Open Access Journals (Sweden)

    I. Herman-Sucharska

    2011-05-01

    Full Text Available Background/Objective: The purpose of the study was"nto compare the diagnostic values of prenatal ultrasound"nand MRI in fetal central nervous system defects."nPatients and Methods: Three-hundred eighty-five"nMRIs were performed in pregnant women with the"nultrasound suspicion of fetal defect. US was conducted"nwith the Voluson-Kretz730PRO. In 158 cases (41%"nfetal CNS defect was found. MR was performed with the"n1.5T system, torso surface coil, SSFSET2 sequence. MR"nresults were compared with prenatal US and verified"nafter the delivery by physical tests, US, TK and surgery"nor in cases of infant death with a pathomorphological"nexamination."nResults: Of 158 infants, eight died after delivery, 93 were"nconsulted in the neurosurgical clinic, 19 underwent a"nneurosurgery treatment and the remaining seven infants'"nfate is unknown. Fetal MRI widened the pertinent US"ndiagnoses in 62%. The 100% compliance is pertained"nto hydrocephalus and anencephaly. US results failed"nin some cases of corpus callosum agenesis, aqueductal"nstenosis, intracranial cyst, holoprosencephaly,"nschizencephaly, Dandy-Walker complex, syringomyelia,"ndiplomyelia and myelomeningocele. In 15 cases, MRI"ncompletely changed the prognosis and treatment"n(holoprosencephaly, myelomeningocoele, diplomyelia,"nintracranial cyst, lung hypoplasia, urinary bladder"nagenesis-not detected during prenatal US. Postnatal"nexaminations and surgery confirmed the results of"nprenatal MRI."nConclusion: MRI compared with prenatal US proved"nbetter effectiveness in imaging of fetal CNS defects,"nespecially in the imaging of the posterior fossa structures,"nthe ventricular system, the corpus callosum, the"nevaluation of meningocoele contents and the complex"nmalformations of the central nervous system.

  7. A CDMA architecture for a Ka-band Personal Access Satellite System

    Science.gov (United States)

    Motamedi, Masoud; Sue, Miles K.

    1990-01-01

    A Code Division Multiple Access (CDMA) architecture is currently being studied for use in a Ka-band Personal Access Satellite System (PASS). The complete architecture consisting of block diagrams of the user terminal, the supplier station, the network management center, and the satellite is described along with the access methods and frequency/time plans. The complexity of developing this system using the CDMA architecture is compared to that of a Frequency Division Multiple Access (FDMA) architecture. The inherent advantages and disadvantages of the two architectures are compared and their respective capacities are discussed.

  8. High-Speed Optical Local Access Network System Using Bi-Directional Polarization Multiplexing

    Institute of Scientific and Technical Information of China (English)

    Mitsuru Miyauchi; Yanjun Sun

    2003-01-01

    A high-speed and economical optical local access network system is proposed where bi-directional polarization multiplexing is applied to a bi-directional transmission. Experimental results using a prototype system confirmlow optical loss and environmental stabilities.

  9. High-Speed Optical Local Access Network System Using Bi-Directional Polarization Multiplexing

    Institute of Scientific and Technical Information of China (English)

    Mitsuru; Miyauchi; Yanjun; Sun

    2003-01-01

    A high-speed and economical optical local access network system is proposed where bi-directional polarization multiplexing is applied to a bi-directional transmission. Experimental results using a prototype system confirm low optical loss and environmental stabilities.

  10. Applying the Earth System Grid Security System in a Heterogeneous Environment of Data Access Services

    Science.gov (United States)

    Kershaw, Philip; Lawrence, Bryan; Lowe, Dominic; Norton, Peter; Pascoe, Stephen

    2010-05-01

    CEDA (Centre for Environmental Data Archival) based at STFC Rutherford Appleton Laboratory is host to the BADC (British Atmospheric Data Centre) and NEODC (NERC Earth Observation Data Centre) with data holdings of over half a Petabyte. In the coming months this figure is set to increase by over one Petabyte through the BADC's role as one of three data centres to host the CMIP5 (Coupled Model Intercomparison Project Phase 5) core archive of climate model data. Quite apart from the problem of managing the storage of such large volumes there is the challenge of collating the data together from the modelling centres around the world and enabling access to these data for the user community. An infrastructure to support this is being developed under the US Earth System Grid (ESG) and related projects bringing together participating organisations together in a federation. The ESG architecture defines Gateways, the web interfaces that enable users to access data and data serving applications organised into Data Nodes. The BADC has been working in collaboration with US Earth System Grid team and other partners to develop a security system to restrict access to data. This provides single sign-on via both OpenID and PKI based means and uses role based authorisation facilitated by SAML and OpenID based interfaces for attribute retrieval. This presentation will provide an overview of the access control architecture and look at how this has been implemented for CEDA. CEDA has developed an expertise in data access and information services over several years through a number of projects to develop and enhance these capabilities. Participation in CMIP5 comes at a time when a number of other software development activities are coming to fruition. New services are in the process of being deployed alongside services making up the system for ESG. The security system must apply access control across this heterogeneous environment of different data services and technologies. One strand

  11. Validation of a Knowledge Transfer Tool for the Knee Inflammation MRI Scoring System for Bone Marrow Lesions According to the OMERACT Filter

    DEFF Research Database (Denmark)

    Jaremko, Jacob L; Azmat, Omar; Lambert, Robert Gw

    2017-01-01

    OBJECTIVE: To assess feasibility and reliability of scoring bone marrow lesions (BML) on knee magnetic resonance imaging (MRI) in osteoarthritis using the Outcome Measures in Rheumatology Knee Inflammation MRI Scoring System (KIMRISS), with a Web-based interface and online training with real-time...

  12. Validation of an anatomical coordinate system for clinical evaluation of the knee joint in upright and closed MRI.

    Science.gov (United States)

    Olender, Gavin; Hurschler, Christof; Fleischer, Benjamin; Friese, Karl-Ingo; Sukau, Andreas; Gutberlet, Marcel; Becher, Christoph

    2014-05-01

    A computerized method to automatically and spatially align joint axes of in vivo knee scans was established and compared to a fixed reference system implanted in a cadaver model. These computational methods to generate geometric models from static MRI images with an automatic coordinate system fitting proved consistent and accurate to reproduce joint motion in multiple scan positions. Two MRI platforms, upright and closed, were used to scan a phantom cadaver knee to create a three-dimensional, geometric model. The knee was subsequently scanned in several positions of knee bending in a custom made fixture. Reference markers fixed to the bone were tracked by an external infrared camera system as well as by direct segmentation from scanned images. Anatomical coordinate systems were automatically fitted to the segmented bone model and the transformations of joint position were compared to the reference marker coordinate systems. The tracked translation and rotation measurements of the automatic coordinate system were found to be below root mean square errors of 0.8 mm and 0.7°. In conclusion, the precision of the translation and rotational tracking is found to be sensitive to the scanning modality, albeit in upright or closed MRI, but still within comparative measures to previously performed studies. The potential to use segmented bone models for patient joint analysis could vastly improve clinical evaluation of disorders of the knee with continual application in future three-dimensional computations.

  13. Quality assurance in functional MRI

    DEFF Research Database (Denmark)

    Liu, Thomas T; Glover, Gary H; Mueller, Bryon A

    2015-01-01

    Over the past 20 years, functional magnetic resonance imaging (fMRI) has ben- efited greatly from improvements in MRI hardware and software. At the same time, fMRI researchers have pushed the technical limits of MRI systems and greatly in- fluenced the development of state-of-the-art systems....... Minimizing image noise and maximizing system stability is critical in fMRI because the blood oxygenation level- dependent (BOLD) signal changes that are used for most fMRI studies represent only a small fraction of the total MR signal. In addition, multiple imaging volumes must be acquired over time to track...... cognitive processes. As a result, MRI scanners must have excellent time-series stability to accurately measure BOLD signal changes over the course of a long time series (typically on the order of 10 min per scan). fMRI studies are particularly demanding on the scanner hardware because they utilize fast...

  14. MRI-based motion correction of thoracic PET: initial comparison of acquisition protocols and correction strategies suitable for simultaneous PET/MRI systems

    Energy Technology Data Exchange (ETDEWEB)

    Dikaios, Nikolaos; Fryer, Tim D. [University of Cambridge, Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, Cambridge (United Kingdom); Izquierdo-Garcia, David; Mani, Venkatesh; Fayad, Zahi A. [Mount Sinai School of Medicine, Imaging Science Laboratories, Translational and Molecular Imaging Institute, Department of Radiology, New York, NY (United States); Graves, Martin J. [University of Cambridge, Department of Radiology, Cambridge (United Kingdom)

    2012-02-15

    Magnetic resonance imaging (MRI) acquired on equipment capable of simultaneous MRI and positron emission tomography (PET) could potentially provide the gold standard method for motion correction of PET. To assess the latter, in this study we compared fast 2D and 3D MRI of the torso and used deformation parameters from real MRI data to correct simulated PET data for respiratory motion. PET sinogram data were simulated using SimSET from a 4D pseudo-PET image series created by segmenting MR images acquired over a respiratory cycle. Motion-corrected PET images were produced using post-reconstruction registration (PRR) and motion-compensated image reconstruction (MCIR). MRI-based motion correction improved PET image quality at the lung-liver and lung-spleen boundaries and in the heart but little improvement was obtained where MRI contrast was low. The root mean square error in SUV units per voxel compared to a motion-free image was reduced from 0.0271 (no motion correction) to 0.0264 (PRR) and 0.0250 (MCIR). Motion correction using MRI can improve thoracic PET images but there are limitations due to the quality of fast MRI. (orig.)

  15. MRI of the Chest

    Medline Plus

    Full Text Available ... provides movie-like sequential imaging of the cardiovascular system that is important to assess the health and ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

  16. MRI of the Chest

    Medline Plus

    Full Text Available ... provides movie-like sequential imaging of the cardiovascular system that is important to assess the health and ... the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not ...

  17. ACCESS TO A COMPUTER SYSTEM. BETWEEN LEGAL PROVISIONS AND TECHNICAL REALITY

    Directory of Open Access Journals (Sweden)

    Maxim DOBRINOIU

    2016-05-01

    Full Text Available Nowadays, on a rise of cybersecurity incidents and a very complex IT&C environment, the national legal systems must adapt in order to properly address the new and modern forms of criminality in cyberspace. The illegal access to a computer system remains one of the most important cyber-related crimes due to its popularity but also from the perspective as being a door opened to computer data and sometimes a vehicle for other tech crimes. In the same time, the information society services slightly changed the IT paradigm and represent the new interface between users and systems. Is true that services rely on computer systems, but accessing services goes now beyond the simple accessing computer systems as commonly understood by most of the legislations. The article intends to explain other sides of the access related to computer systems and services, with the purpose to advance possible legal solutions to certain case scenarios.

  18. The storage system of PCM based on random access file system

    Science.gov (United States)

    Han, Wenbing; Chen, Xiaogang; Zhou, Mi; Li, Shunfen; Li, Gezi; Song, Zhitang

    2016-10-01

    Emerging memory technologies such as Phase change memory (PCM) tend to offer fast, random access to persistent storage with better scalability. It's a hot topic of academic and industrial research to establish PCM in storage hierarchy to narrow the performance gap. However, the existing file systems do not perform well with the emerging PCM storage, which access storage medium via a slow, block-based interface. In this paper, we propose a novel file system, RAFS, to bring about good performance of PCM, which is built in the embedded platform. We attach PCM chips to the memory bus and build RAFS on the physical address space. In the proposed file system, we simplify traditional system architecture to eliminate block-related operations and layers. Furthermore, we adopt memory mapping and bypassed page cache to reduce copy overhead between the process address space and storage device. XIP mechanisms are also supported in RAFS. To the best of our knowledge, we are among the first to implement file system on real PCM chips. We have analyzed and evaluated its performance with IOZONE benchmark tools. Our experimental results show that the RAFS on PCM outperforms Ext4fs on SDRAM with small record lengths. Based on DRAM, RAFS is significantly faster than Ext4fs by 18% to 250%.

  19. Activation of Visuomotor Systems during Visually Guided Movements: A Functional MRI Study

    Science.gov (United States)

    Ellermann, Jutta M.; Siegal, Joel D.; Strupp, John P.; Ebner, Timothy J.; Ugurbil, Kâmil

    1998-04-01

    The dorsal stream is a dominant visuomotor pathway that connects the striate and extrastriate cortices to posterior parietal areas. In turn, the posterior parietal areas send projections to the frontal primary motor and premotor areas. This cortical pathway is hypothesized to be involved in the transformation of a visual input into the appropriate motor output. In this study we used functional magnetic resonance imaging (fMRI) of the entire brain to determine the patterns of activation that occurred while subjects performed a visually guided motor task. In nine human subjects, fMRI data were acquired on a 4-T whole-body MR system equipped with a head gradient coil and a birdcage RF coil using aT*2-weighted EPI sequence. Functional activation was determined for three different tasks: (1) a visuomotor task consisting of moving a cursor on a screen with a joystick in relation to various targets, (2) a hand movement task consisting of moving the joystick without visual input, and (3) a eye movement task consisting of moving the eyes alone without visual input. Blood oxygenation level-dependent (BOLD) contrast-based activation maps of each subject were generated using period cross-correlation statistics. Subsequently, each subject's brain was normalized to Talairach coordinates, and the individual maps were compared on a pixel by pixel basis. Significantly activated pixels common to at least four out of six subjects were retained to construct the final functional image. The pattern of activation during visually guided movements was consistent with the flow of information from striate and extrastriate visual areas, to the posterior parietal complex, and then to frontal motor areas. The extensive activation of this network and the reproducibility among subjects is consistent with a role for the dorsal stream in transforming visual information into motor behavior. Also extensively activated were the medial and lateral cerebellar structures, implicating the cortico

  20. Providing Internet Access to the Ohio Career Information System for All Residents: A Feasibility Study.

    Science.gov (United States)

    Lewis, Morgan V.

    Expanded Internet access to the Ohio Career Information System (OCIS) would provide adults in Ohio who need to or wish to make career changes with the best available information about occupations, education and training programs, and financial aid. In order to determine the feasibility of improving access without cost to users, an advisory group,…

  1. 77 FR 48199 - Privacy Act; System of Records: State-35, Information Access Programs Records

    Science.gov (United States)

    2012-08-13

    ... user must first be granted access to the Department of State computer system. All employees of the... trails of access from the computer media, thereby permitting regular and ad hoc monitoring of computer usage. RETENTION AND DISPOSAL: Records are retired and destroyed in accordance with published...

  2. Evaluation on the Occupational Information Access System as Used at Churchill High School. A Project Report.

    Science.gov (United States)

    McKinlay, Bruce; Adams, Daniel

    The Occupational Information Access System (OIAS) improves the accessibility of occupational labor market information for career planning. Its operation at Churchill High School is evaluated from several angels: the likes and dislikes of users; the effect of OIAS on users' knowledge of occupational information and on their career plans; why other…

  3. A Generic Role Based Access Control Model for Wind Power Systems

    DEFF Research Database (Denmark)

    Nagarajan, Anand; Jensen, Christian D.

    2010-01-01

    infrastructure in a software domain in a manufacturer independent manner as well as establishing secure communication and authenticating the other parties in electrical power infrastructures, but they do not address the problem of access control. We therefore propose a generic model for access control in wind...... power systems, which is based on the widely used role-based access control model. The proposed model is tested using a prototype designed in conformance with the standards that are in use in modern wind power infrastructure and the results are presented to determine the overhead in communication caused...... while adhering to the proposed access model....

  4. Access Requirement Analysis of E-Governance Systems

    Science.gov (United States)

    Kim, Tai-Hoon

    The strategic and contemporary importance of e-governance has been recognized across the world. In India too, various ministries of Govt. of India and State Governments have taken e-governance initiatives to provide e-services to citizens and the business they serve. To achieve the mission objectives, and make such e-governance initiatives successful it would be necessary to improve the trust and confidence of the stakeholders. It is assumed that the delivery of government services will share the same public network information that is being used in the community at large. In particular, the Internet will be the principal means by which public access to government and government services will be achieved. To provide the security measures main aim is to identify user's access requirement for the stakeholders and then according to the models of Nath's approach. Based on this analysis, the Govt. can also make standards of security based on the e-governance models. Thus there will be less human errors and bias. This analysis leads to the security architecture of the specific G2C application.

  5. An iterative method for coil sensitivity estimation in multi-coil MRI systems.

    Science.gov (United States)

    Ling, Qiang; Li, Zhaohui; Song, Kaikai; Li, Feng

    2014-12-01

    This paper presents an iterative coil sensitivity estimation method for multi-coil MRI systems. The proposed method works with coil images in the magnitude image domain. It determines a region of support (RoS), a region being composed of the same type of tissues, by a region growing algorithm, which makes use of both intensities and intensity gradients of pixels. By repeating this procedure, it can determine multiple regions of support, which together cover most of the concerned image area. The union of these regions of support provides a rough estimate of the sensitivity of each coil through dividing the intensities of pixels by the average intensity inside every region of support. The obtained rough coil sensitivity estimate is further approached with the product of multiple low-order polynomials, rather than a single one. The product of these polynomials provides a smooth estimate of the sensitivity of each coil. With the obtained sensitivities of coils, it can produce a better reconstructed image, which determines more correct regions of support and yields preciser estimates of the sensitivities of coils. In other words, the method can be iteratively implemented to improve the estimation performance. The proposed method was verified through both simulated data and clinical data from different body parts. The experimental results confirm the superiority of our method to some conventional methods.

  6. Application of extracellular gadolinium-based MRI contrast agents and the risk of nephrogenic systemic fibrosis.

    Science.gov (United States)

    Heverhagen, J T; Krombach, G A; Gizewski, E

    2014-07-01

    Nephrogenic systemic fibrosis (NSF) is a serious, sometimes fatal disease. Findings in recent years have shown that a causal association between gadolinium containing contrast media and NSF is most likely. Therefore, the regulatory authorities have issued guidelines on the use of gadolinium-containing contrast media which have reduced the number of new cases of NSF to almost zero. However, it is for precisely this reason that the greatest care must still be taken to ensure that these guidelines are complied with. The most important factors are renal function, the quantity of gadolinium administered and coexisting diseases such as inflammation. All of these factors crucially influence the quantity of gadolinium released from the chelat in the body. This free gadolinium is thought to be the trigger for NSF. Other important factors are the stability of the gadolinium complex and furthermore the route of its elimination from the body. Partial elimination via the liver might be an additional protective mechanism. In conclusion, despite the NSF risk, contrast-enhanced MRI is a safe diagnostic procedure which can be used reliably and safely even in patients with severe renal failure, and does not necessarily have to be replaced by other methods.

  7. Clinical evaluation of a computer-aided diagnosis system for determining cancer aggressiveness in prostate MRI

    Energy Technology Data Exchange (ETDEWEB)

    Litjens, Geert J.S.; Barentsz, Jelle O.; Karssemeijer, Nico; Huisman, Henkjan J. [Radboud University Medical Center, Department of Radiology, Nijmegen (Netherlands)

    2015-11-15

    To investigate the added value of computer-aided diagnosis (CAD) on the diagnostic accuracy of PIRADS reporting and the assessment of cancer aggressiveness. Multi-parametric MRI and histopathological outcome of MR-guided biopsies of a consecutive set of 130 patients were included. All cases were prospectively PIRADS reported and the reported lesions underwent CAD analysis. Logistic regression combined the CAD prediction and radiologist PIRADS score into a combination score. Receiver-operating characteristic (ROC) analysis and Spearman's correlation coefficient were used to assess the diagnostic accuracy and correlation to cancer grade. Evaluation was performed for discriminating benign lesions from cancer and for discriminating indolent from aggressive lesions. In total 141 lesions (107 patients) were included for final analysis. The area-under-the-ROC-curve of the combination score was higher than for the PIRADS score of the radiologist (benign vs. cancer, 0.88 vs. 0.81, p = 0.013 and indolent vs. aggressive, 0.88 vs. 0.78, p < 0.01). The combination score correlated significantly stronger with cancer grade (0.69, p = 0.0014) than the individual CAD system or radiologist (0.54 and 0.58). Combining CAD prediction and PIRADS into a combination score has the potential to improve diagnostic accuracy. Furthermore, such a combination score has a strong correlation with cancer grade. (orig.)

  8. MRI Scans

    Science.gov (United States)

    Magnetic resonance imaging (MRI) uses a large magnet and radio waves to look at organs and structures inside your body. Health care professionals use MRI scans to diagnose a variety of conditions, from ...

  9. Shoulder MRI

    Science.gov (United States)

    ... MRI scanners are air-conditioned and well-lit. Music may be played through the headphones to help ... that magnetic resonance imaging harms the fetus, pregnant women usually are advised not to have an MRI ...

  10. TECHNOLOGY FOR ADMINISTERING OF THE ACCESS TO INFORMATION RESOURCES IN MANAGEMENT SYSTEM ON THE AVIATION ENTERPRISE

    Directory of Open Access Journals (Sweden)

    Andrey V. Degtyarev

    2015-01-01

    Full Text Available The task of administering software-information complex occurs duringthe development of application systems for managing business-processes and is connected with the organization of access forusers to information resources in conditions of multi-user information systems for management. For solution of this problem proposed theapproach, which is based on a hierarchical system of access rightsto information resources on the levels: tool, object and procedural.Keywords: software-information complex, information resources,administering, permissions, separation of powers, access model.

  11. Whole-body MRI: comprehensive evaluation on a 48-channel 3T MRI system in less than 40 minutes. Preliminary results

    Directory of Open Access Journals (Sweden)

    Mateus de Andrade Hernandes

    2012-12-01

    Full Text Available OBJECTIVE: To evaluate a comprehensive MRI protocol that investigates for cancer, vascular disease, and degenerative/inflammatory disease from the head to the pelvis in less than 40 minutes on a new generation 48-channel 3T system. MATERIALS AND METHODS: All MR studies were performed on a 48-channel 3T MR scanner. A 20-channel head/neck coil, two 18-channel body arrays, and a 32-channel spine array were employed. A total of 4 healthy individuals were studied. The designed protocol included a combination of single-shot T2-weighted sequences, T1-weighted 3D gradient-echo pre- and post-gadolinium. All images were retrospectively evaluated by two radiologists independently for overall image quality. RESULTS: The image quality for cancer was rated as excellent in the liver, pancreas, kidneys, lungs, pelvic organs, and brain, and rated as fair in the colon and breast. For vascular diseases ratings were excellent in the aorta, major branch vessel origins, inferior vena cava, portal and hepatic veins, rated as good in pulmonary arteries, and as poor in the coronary arteries. For degenerative/inflammatory diseases ratings were excellent in the brain, liver and pancreas. The inter-observer agreement was excellent. CONCLUSION: A comprehensive and time efficient screening for important categories of disease processes may be achieved with high quality imaging in a new generation 48-channel 3T system.

  12. Whole-body MRI: comprehensive evaluation on a 48-channel 3T MRI system in less than 40 minutes. Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Hernandes, Mateus de Andrade; Semelka, Richard C.; Bamrungchart, Saraporn; Stallings, Clifton, E-mail: richsem@med.unc.edu [Department of Radiology, University of North Carolina, Chapel Hill, NC (United States); Elias Junior, Jorge [Imaging and Medical Physics Center, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP (Brazil); Dale, Brian M. [Siemens Medical Solutions USA, Inc., Cary, NC (United States)

    2012-11-15

    Objective: To evaluate a comprehensive MRI protocol that investigates for cancer, vascular disease, and degenerative/inflammatory disease from the head to the pelvis in less than 40 minutes on a new generation 48-channel 3T system. Materials and Methods: All MR studies were performed on a 48-channel 3T MR scanner. A 20-channel head/neck coil, two 18-channel body arrays, and a 32-channel spine array were employed. A total of 4 healthy individuals were studied. The designed protocol included a combination of single-shot T2-weighted sequences, T1-weighted 3D gradient echo pre- and post-gadolinium. All images were retrospectively evaluated by two radiologists independently for overall image quality. Results: The image quality for cancer was rated as excellent in the liver, pancreas, kidneys, lungs, pelvic organs, and brain, and rated as fair in the colon and breast. For vascular diseases ratings were excellent in the aorta, major branch vessel origins, inferior vena cava, portal and hepatic veins, rated as good in pulmonary arteries, and as poor in the coronary arteries. For degenerative/inflammatory diseases ratings were excellent in the brain, liver and pancreas. The inter-observer agreement was excellent. Conclusion: A comprehensive and time efficient screening for important categories of disease processes may be achieved with high quality imaging in a new generation 48-channel 3T system. (author)

  13. Neural Response during the Activation of the Attachment System in Patients with Borderline Personality Disorder: An fMRI Study

    OpenAIRE

    Buchheim, Anna; Erk, Susanne; George, Carol; Kächele, Horst; Martius, Philipp; Pokorny, Dan; Spitzer, Manfred; Walter, Henrik

    2016-01-01

    Individuals with borderline personality disorder (BPD) are characterized by emotional instability, impaired emotion regulation and unresolved attachment patterns associated with abusive childhood experiences. We investigated the neural response during the activation of the attachment system in BPD patients compared to healthy controls using functional magnetic resonance imaging (fMRI). Eleven female patients with BPD without posttraumatic stress disorder (PTSD) and 17 healthy female controls ...

  14. A Fault-Tolerant Emergency-Aware Access Control Scheme for Cyber-Physical Systems

    CERN Document Server

    Wu, Guowei; Xia, Feng; Yao, Lin

    2012-01-01

    Access control is an issue of paramount importance in cyber-physical systems (CPS). In this paper, an access control scheme, namely FEAC, is presented for CPS. FEAC can not only provide the ability to control access to data in normal situations, but also adaptively assign emergency-role and permissions to specific subjects and inform subjects without explicit access requests to handle emergency situations in a proactive manner. In FEAC, emergency-group and emergency-dependency are introduced. Emergencies are processed in sequence within the group and in parallel among groups. A priority and dependency model called PD-AGM is used to select optimal response-action execution path aiming to eliminate all emergencies that occurred within the system. Fault-tolerant access control polices are used to address failure in emergency management. A case study of the hospital medical care application shows the effectiveness of FEAC.

  15. A motorized ultrasound system for MRI-ultrasound fusion guided prostatectomy

    Science.gov (United States)

    Seifabadi, Reza; Xu, Sheng; Pinto, Peter; Wood, Bradford J.

    2016-03-01

    Purpose: This study presents MoTRUS, a motorized transrectal ultrasound system, to enable remote navigation of a transrectal ultrasound (TRUS) probe during da Vinci assisted prostatectomy. MoTRUS not only provides a stable platform to the ultrasound probe, but also allows the physician to navigate it remotely while sitting on the da Vinci console. This study also presents phantom feasibility study with the goal being intraoperative MRI-US image fusion capability to bring preoperative MR images to the operating room for the best visualization of the gland, boundaries, nerves, etc. Method: A two degree-of-freedom probe holder is developed to insert and rotate a bi-plane transrectal ultrasound transducer. A custom joystick is made to enable remote navigation of MoTRUS. Safety features have been considered to avoid inadvertent risks (if any) to the patient. Custom design software has been developed to fuse pre-operative MR images to intraoperative ultrasound images acquired by MoTRUS. Results: Remote TRUS probe navigation was evaluated on a patient after taking required consents during prostatectomy using MoTRUS. It took 10 min to setup the system in OR. MoTRUS provided similar capability in addition to remote navigation and stable imaging. No complications were observed. Image fusion was evaluated on a commercial prostate phantom. Electromagnetic tracking was used for the fusion. Conclusions: Motorized navigation of the TRUS probe during prostatectomy is safe and feasible. Remote navigation provides physician with a more precise and easier control of the ultrasound image while removing the burden of manual manipulation of the probe. Image fusion improved visualization of the prostate and boundaries in a phantom study.

  16. MRI assessment of lumbar intervertebral disc degeneration with lumbar degenerative disease using the Pfirrmann grading systems.

    Directory of Open Access Journals (Sweden)

    Li-Peng Yu

    Full Text Available BACKGROUND: To evaluate by MRI intervertebral disc degeneration in patients with lumbar degenerative disease using the Pfirrmann grading system and to determine whether Modic changes correlated with the Pfirrmann grades and modified Pfirrmann grades of disc degeneration. METHODS: The clinical data of 108 surgical patients with lumbar degenerative disease were reviewed and their preoperative MR images were analyzed. Disc degeneration was evaluated using the Pfirrmann grading system. Patients were followed up and low back pain was evaluated using the visual analog scale (VAS and the effect of back pain on the daily quality of life was assessed using Oswestry disability index (ODI. RESULTS: Forty-four cases had normal anatomical appearance (Modic type 0 and their Pfirrmann grades were 3.77±0.480 and their modified Pfirrmann grades were of 5.81±1.006. Twenty-seven cases had Modic type I changes and their Pfirrmann grades were 4.79±0.557 and their modified Pfirrmann grades were 7.00±0.832. Thirty-six cases exhibited Modic type II changes and their Pfirrmann grades and modified Pfirrmann grades were 4.11±0.398 and 6.64±0.867, respectively. One case had Modic type III changes. Kruskal-Wallis test revealed significant difference in modified Pfirrmann grade among Modic type 0, I and II changes (P0.05. Binary regression analysis showed that Modic changes correlated most strongly with disc degeneration. Follow up studies indicated that the VAS and ODI scores were markedly improved postoperatively. However, no difference was noted in VAS and ODI scores among patients with different Modic types. CONCLUSION: Modic changes correlate with the Pfirrmann and modified Pfirrmann grades of disc degeneration in lumbar degenerative disease. There is no significant correlation between Modic types and surgical outcomes.

  17. Hemodynamic characteristics of the vertebrobasilar system analyzed using MRI-based models.

    Directory of Open Access Journals (Sweden)

    Amanda K Wake-Buck

    Full Text Available The vertebrobasilar system (VBS is unique in human anatomy in that two arteries merge into a single vessel, and it is especially important because it supplies the posterior circulation of the brain. Atherosclerosis develops in this region, and atherosclerotic plaques in the vertebrobasilar confluence can progress with catastrophic consequences, including artery occlusion. Quantitative assessments of the flow characteristics in the VBS could elucidate the factors that influence flow patterns in this confluence, and deviations from normal patterns might then be used to predict locations to monitor for potential pathological changes, to detect early signs of disease, and to evaluate treatment options and efficacy. In this study, high-field MRI was used in conjunction with computational fluid dynamics (CFD modeling to investigate the hemodynamics of subject-specific confluence models (n = 5 and to identify different geometrical classes of vertebrobasilar systems (n = 12 of healthy adult subjects. The curvature of the vessels and their mutual orientation significantly affected flow parameters in the VBS. The basilar artery geometry strongly influenced both skewing of the velocity profiles and the wall shear stress distributions in the VBS. All five subjects modeled possessed varying degrees of vertebral asymmetry, and helical flow was observed in four cases, suggesting that factors other than vertebral asymmetry influence mixing of the vertebral artery flow contributions. These preliminary studies verify that quantitative, MR imaging techniques in conjunction with subject-specific CFD models of healthy adult subjects may be used to characterize VBS hemodynamics and to predict flow features that have been related to the initiation and development of atherosclerosis in large arteries. This work represents an important first step towards applying this approach to study disease initiation and progression in the VBS.

  18. Experimental MRI-SPECT insert system with Hybrid Semiconductor detectors Timepix for MR animal scanner Bruker 47/20

    Science.gov (United States)

    Zajicek, J.; Burian, M.; Soukup, P.; Novak, V.; Macko, M.; Jakubek, J.

    2017-01-01

    Multimodal medical imaging based on Magnetic Resonance is mainly combinated with one of the scintigraphic method like PET or SPECT. These methods provide functional information whereas magnetic resonance imaging provides high spatial resolution of anatomical information or complementary functional information. Fusion of imaging modalities allows researchers to obtain complimentary information in a single measurement. The combination of MRI with SPECT is still relatively new and challenging in many ways. The main complication of using SPECT in MRI systems is the presence of a high magnetic field therefore (ferro)magnetic materials have to be eliminated. Furthermore the application of radiofrequency fields within the MR gantry does not allow for the use of conductive structures such as the common heavy metal collimators. This work presents design and construction of an experimental MRI-SPECT insert system and its initial tests. This unique insert system consists of an MR-compatible SPECT setup with CdTe pixelated sensors Timepix tungsten collimators and a radiofrequency coil. Measurements were performed on a gelatine and tissue phantom with an embedded radioisotopic source (57Co 122 keV γ ray) inside the RF coil by the Bruker BioSpec 47/20 (4.7 T) MR animal scanner. The project was performed in the framework of the Medipix Collaboration.

  19. Access to E-learning in the Nigerian university system (NUS): a case ...

    African Journals Online (AJOL)

    Access to E-learning in the Nigerian university system (NUS): a case study of ... based programmes during an e- learning workshop organized by AfriHUB. ... Lecturers and students employ ICT facilities for teaching and learning respectively.

  20. Asynchronous Free-Space Optical CDMA Communications System for Last-mile Access Network

    DEFF Research Database (Denmark)

    Jurado-Navas, Antonio; Raddo, Thiago R.; Sanches, Anderson L.

    2016-01-01

    We propose a new hybrid asynchronous OCDMA-FSO communications system for access network solutions. New ABER expressions are derived under gamma-gamma scintillation channels, where all users can surprisingly achieve error-free transmissions when FEC is employed....

  1. Sandia Engineering Analysis Code Access System v. 2.0.1

    Energy Technology Data Exchange (ETDEWEB)

    2017-10-30

    The Sandia Engineering Analysis Code Access System (SEACAS) is a suite of preprocessing, post processing, translation, visualization, and utility applications supporting finite element analysis software using the Exodus database file format.

  2. 75 FR 4101 - Enterprise Income Verification (EIV) System User Access Authorization Form and Rules of Behavior...

    Science.gov (United States)

    2010-01-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT Enterprise Income Verification (EIV) System User Access Authorization Form and Rules.... This notice also lists the following information: Title of Proposal: Enterprise Income Verification...

  3. Effect of insulating layer material on RF-induced heating for external fixation system in 1.5 T MRI system.

    Science.gov (United States)

    Liu, Yan; Kainz, Wolfgang; Qian, Songsong; Wu, Wen; Chen, Ji

    2014-09-01

    The radio frequency (RF)-induced heating is a major concern when patients with medical devices are placed inside a magnetic resonance imaging (MRI) system. In this article, numerical studies are applied to investigate the potentials of using insulated materials to reduce the RF heating for external fixation devices. It is found that by changing the dielectric constant of the insulation material, the RF-induced heating at the tips of devices can be altered. This study indicates a potential technique of developing external fixation device with low MRI RF heating.

  4. A Fine-Grained Data Access Control System in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Boniface K. Alese

    2015-12-01

    Full Text Available The evolving realities of Wireless Sensor Network (WSN deployed to various terrain of life require serving multiple applications. As large amount of sensed data are distributed and stored in individual sensors nodes, the illegal access to these sensitive data can be devastating. Consequently, data insecurity becomes a big concern. This study, therefore, proposes a fine-grained access control system which only requires the right set of users to access a particular data, based on their access privileges in the sensor networks. It is designed using Priccess Protocol with Access policy formulation adopting the principle of Bell Lapadula model as well as Attribute-Based Encryption (ABE to control access to sensor data. The functionality of the proposed system is simulated using Netbeans. The performance analysis of the proposed system using execution time and size of the key show that the higher the key size, the harder it becomes for the attacker to hack the system. Additionally, the time taken for the proposed work is lesser which makes the work faster than the existing work. Consequently, a well secure interactive web-based application that could facilitates the field officers access to stored data in safe and secure manner is developed.

  5. Economically adapted transmission systems in open access schemes -- Application of genetic algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Rudnick, H.; Palma, R.; Cura, E.; Silva, C. [Pontificia Univ. Catolica de Chile, Santiago (Chile). Dept. de Ingenieria Electrica

    1996-08-01

    A dynamic transmission planning methodology using a genetic algorithm is formulated for the purpose of determining an economically adapted electric transmission system in a deregulated open access environment. Transmission investment sensitivity information linked to short term marginal income is used. A computer program is developed and applied to obtain a long range adapted transmission grid for the Chilean electrical system. Two open access pricing methodologies are evaluated in a spot price framework, as applied to the adapted grid over the time horizon.

  6. Utility-Interconnected Photovoltaic Systems: Evaluating the Rationale for the Utility-Accessible External Disconnect Switch

    Energy Technology Data Exchange (ETDEWEB)

    Coddington, M.; Margolis, R.M.; Aabakken, J.

    2008-01-01

    The utility-accessible alternating current (AC) external disconnect switch (EDS) for distributed generators, including photovoltaic (PV) systems, is a hardware feature that allows a utility?s employees to manually disconnect a customer-owned generator from the electricity grid. This paper examines the utility-accessible EDS debate in the context of utility-interactive PV systems for residential and small commercial installations. It also evaluates the rationale for EDS requirements.

  7. Key issues of multiple access technique for LEO satellite communication systems

    Institute of Scientific and Technical Information of China (English)

    温萍萍; 顾学迈

    2004-01-01

    The large carrier frequency shift caused by the high-speed movement of satellite (Doppler effects) and the propagation delay on the up-down link are very critical issues in an LEO satellite communication system, which affects both the selection and the implementation of a suitable access method. A Doppler based multiple access technique is used here to control the flow and an MPRMA-HS protocol is proposed for the application in LEO satellite communication systems. The extended simulation trials prove that the proposed scheme seems to be a very promising access method.

  8. Evaluation of malformations of the fetal central nervous system using fetal MRI; Das fetale MRT in der praenatalen Beurteilung von ZNS-Stoerungen

    Energy Technology Data Exchange (ETDEWEB)

    Blondin, D. [Inst. fuer Diagnostische Radiologie, Universitaetsklinikum Duesseldorf (Germany); Schaper, J.; Klee, D.; Moedder, U. [Inst. fuer Diagnostische Radiologie, Kinderradiologie, Universitaetsklinikum Duesseldorf (Germany); Reihs, T. [Frauenklinik, Universitaetsklinikum Duesseldorf (Germany); Hammer, R. [Gemeinschaftspraxis, Praenatal-Medizin und Genetik, Duesseldorf (Germany); Messing-Juenger, M. [Abt. Neurochirurgie, Klinik Sankt Augustin (Germany)

    2008-08-15

    Purpose: ultrasound as the primary prenatal screening modality is used to detect fetal anomalies. Aim of the study was to prove the additional value of fetal magnetic resonance imaging (MRI). Materials and methods: in 25 pregnant women (age 30.6 {+-} 4.8; 24 single and one twin pregnancy) with pathologic findings of the central nervous system detected by obstetric ultrasound, a fetal MRI was performed. All sequences (T2w-HASTE, TRUEFISP, T1w-FLASH 2D, DWI) were performed using the breath-hold technique. The results were compared to postnatal MRI or ultrasound scan findings and tested for correlation with the clinical course and development of these children. Results: three to seven days after ultrasound, an MRI of all 26 fetuses without sedation was performed (26.6 {+-} 4.0 GW). One healthy twin was not included in this study. MRI confirmed the ultrasonographic diagnosis in 7 cases. Compared to ultrasound, an additional pathology could be detected by MRI in 8 cases. In 10 cases ultrasound diagnosis was overruled by MRI. Prenatal MRI findings were confirmed by postnatal imaging in 18 children. The clinical course was predictable in 8 of 15 cases, depending on the pathology detected. Three newborns died in the perinatal period. (orig.)

  9. Thermodynamic Entropy and the Accessible States of Some Simple Systems

    Science.gov (United States)

    Sands, David

    2008-01-01

    Comparison of the thermodynamic entropy with Boltzmann's principle shows that under conditions of constant volume the total number of arrangements in a simple thermodynamic system with temperature-independent constant-volume heat capacity, C, is T[superscript C/k]. A physical interpretation of this function is given for three such systems: an…

  10. The new biometric access control system resembles a big electronic eye. It will be used to control access to the LHC from 2007 onwards.

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The new LHC access control systems will soon be using the latest technology: optical recognition based on iris image data. In order to gain access to the tunnel it will be your eye, not your credentials that you'll be required to show! As of September, the entrance point at Point 8 should be the first to be fitted out with iris recognition equipment. The other access shafts will then gradually be equipped one by one.

  11. Visual Cortex Plasticity Following Peripheral Damage To The Visual System: fMRI Evidence.

    Science.gov (United States)

    Lemos, João; Pereira, Daniela; Castelo-Branco, Miguel

    2016-10-01

    Over the last two decades, functional magnetic resonance imaging (fMRI) has become a powerful research method to investigate cortical visual plasticity. Abnormal fMRI response patterns have been occasionally detected in the visually deprived cortex of patients with bilateral retinal diseases. Controversy remains whether these observations indicate structural reorganization of the visual cortex or unmasking of previously silent cortico-cortical connections. In optic nerve diseases, there is weak evidence showing that early visual cortex seems to lack reorganization, while higher-order visual areas undergo plastic changes which may contribute to optimise visual function. There is however accumulating imaging evidence demonstrating trans-synaptic degeneration of the visual cortex in patients with disease of the anterior visual pathways. This may preclude the use of restorative treatments in these patients. Here, we review and update the body of fMRI evidence on visual cortical plasticity.

  12. Coupled circuit numerical analysis of eddy currents in an open MRI system.

    Science.gov (United States)

    Akram, Md Shahadat Hossain; Terada, Yasuhiko; Keiichiro, Ishi; Kose, Katsumi

    2014-08-01

    We performed a new coupled circuit numerical simulation of eddy currents in an open compact magnetic resonance imaging (MRI) system. Following the coupled circuit approach, the conducting structures were divided into subdomains along the length (or width) and the thickness, and by implementing coupled circuit concepts we have simulated transient responses of eddy currents for subdomains in different locations. We implemented the Eigen matrix technique to solve the network of coupled differential equations to speed up our simulation program. On the other hand, to compute the coupling relations between the biplanar gradient coil and any other conducting structure, we implemented the solid angle form of Ampere's law. We have also calculated the solid angle for three dimensions to compute inductive couplings in any subdomain of the conducting structures. Details of the temporal and spatial distribution of the eddy currents were then implemented in the secondary magnetic field calculation by the Biot-Savart law. In a desktop computer (Programming platform: Wolfram Mathematica 8.0®, Processor: Intel(R) Core(TM)2 Duo E7500 @ 2.93GHz; OS: Windows 7 Professional; Memory (RAM): 4.00GB), it took less than 3min to simulate the entire calculation of eddy currents and fields, and approximately 6min for X-gradient coil. The results are given in the time-space domain for both the direct and the cross-terms of the eddy current magnetic fields generated by the Z-gradient coil. We have also conducted free induction decay (FID) experiments of eddy fields using a nuclear magnetic resonance (NMR) probe to verify our simulation results. The simulation results were found to be in good agreement with the experimental results. In this study we have also conducted simulations for transient and spatial responses of secondary magnetic field induced by X-gradient coil. Our approach is fast and has much less computational complexity than the conventional electromagnetic numerical simulation

  13. The neural system that bridges reward and cognition in humans: An fMRI study

    Science.gov (United States)

    Pochon, J. B.; Levy, R.; Fossati, P.; Lehericy, S.; Poline, J. B.; Pillon, B.; Le Bihan, D.; Dubois, B.

    2002-01-01

    We test the hypothesis that motivational and cognitive processes are linked by a specific neural system to reach maximal efficiency. We studied six normal subjects performing a working memory paradigm (n-back tasks) associated with different levels of monetary reward during an fMRI session. The study showed specific brain activation in relation with changes in both the cognitive loading and the reward associated with task performance. First, the working memory tasks activated a network including the dorsolateral prefrontal cortex [Brodmann area (BA) 9/46] and, in addition, in the lateral frontopolar areas (BA 10), but only in the more demanding condition (3-back task). This result suggests that lateral prefrontal areas are organized in a caudo-rostral continuum in relation with the increase in executive requirement. Second, reward induces an increased activation in the areas already activated by working memory processing and in a supplementary region, the medial frontal pole (BA 10), regardless of the level of cognitive processing. It is postulated that the latter region plays a specific role in monitoring the reward value of ongoing cognitive processes. Third, we detected areas where the signal decreases (ventral-BA 11/47 and subgenual prefrontal cortices) in relation with both the increase of cognitive demand and the reward. The deactivation may represent an emotional gating aimed at inhibiting adverse emotional signals to maximize the level of performance. Taken together, these results suggest a balance between increasing activity in cortical cognitive areas and decreasing activity in the limbic and paralimbic structures during ongoing higher cognitive processing. PMID:11960021

  14. Identifying brain systems for gaze orienting during reading: fMRI investigation of the Landolt paradigm

    Directory of Open Access Journals (Sweden)

    Rebekka eHillen

    2013-07-01

    Full Text Available The Landolt reading paradigm was created in order to dissociate effects of eye movements and attention from lexical, syntactic, and sub-lexical processing. While previous eye-tracking and behavioural findings support the usefulness of the paradigm, it remains to be shown that the paradigm actually relies on the brain networks for occulomotor control and attention, but not on systems for lexical/syntactic/orthographic processing. Here, 20 healthy volunteers underwent fMRI scanning while reading sentences (with syntax or unconnected lists of written stimuli (no syntax consisting of words (with semantics or pseudowords (no semantics. In an additional "Landolt reading" condition, all letters were replaced by closed circles, which should be scanned for targets (Landolt's rings in a reading-like fashion from left to right. A conjunction analysis of all five conditions revealed the visual scanning network which involved bilateral visual cortex, premotor cortex, and superior parietal cortex, but which did not include regions for semantics, syntax, or orthography. Contrasting the Landolt reading condition with all other regions revealed additional involvement of the right superior parietal cortex (areas 7A/7P/7PC and postcentral gyrus (area 2 involved in deliberate gaze shifting. These neuroimaging findings demonstrate for the first time that the linguistic and orthographic brain network can be dissociated from a pure gaze-orienting network with the Landolt paradigm. Consequently, the Landolt paradigm may provide novel insights into the contributions of linguistic and non-linguistic factors on reading failure e.g. in developmental dyslexia.

  15. RF Head Coil Design with Improved RF Magnetic Near-Fields Uniformity for Magnetic Resonance Imaging (MRI) Systems.

    Science.gov (United States)

    Sohn, Sung-Min; DelaBarre, Lance; Gopinath, Anand; Vaughan, John Thomas

    2014-08-01

    Higher magnetic field strength in magnetic resonance imaging (MRI) systems offers higher signal-to-noise ratio (SNR), contrast, and spatial resolution in MR images. However, the wavelength in ultra-high fields (7 tesla and beyond) becomes shorter than the human body at the Larmor frequency with increasing static magnetic field (B0) of MRI system. At short wavelengths, interference effect appears resulting in non- uniformity of the RF magnetic near-field (B1) over the subject and MR images may have spatially anomalous contrast. The B1 near-field generated by the transverse electromagnetic (TEM) RF coil's microstrip line element has a maximum near the center of its length and falls off towards both ends. In this study, a double trapezoidal shaped microstrip transmission line element is proposed to obtain uniform B1 field distribution by gradual impedance variation. Two multi-channel RF head coils with uniform and trapezoidal shape elements were built and tested with a phantom at 7T MRI scanner for comparison. The simulation and experimental results show stronger and more uniform B1(+) near-field with the trapezoidal shape.

  16. Design and implementation of a simple multinuclear MRI system for ultra high-field imaging of animals

    Science.gov (United States)

    Choi, Chang-Hoon; Ha, YongHyun; Veeraiah, Pandichelvam; Felder, Jörg; Möllenhoff, Klaus; Shah, N. Jon

    2016-12-01

    Non-proton MRI has recently garnered gathering interest with the increased availability of ultra high-field MRI system. Assuming the availability of a broadband RF amplifier, performing multinuclear MR experiments essentially requires additional hardware, such as an RF resonator and a T/R switch for each nucleus. A double- or triple-resonant RF probe is typically constructed using traps or PIN-diode circuits, but this approach degrades the signal-to-noise ratio (SNR) and image quality compared to a single-resonant coil and this is a limiting factor. In this work, we have designed the required hardware for multinuclear MR imaging experiments employing six single-resonant coil sets and a purpose-built animal bed; these have been implemented into a home-integrated 9.4 T preclinical MRI scanner. System capabilities are demonstrated by distinguishing concentration differences and sensitivity of X-nuclei imaging and spectroscopy without SNR penalty for any nuclei, no subject interruption and no degradation of the static shim conditions.

  17. Towards a Reference Model for Open Access and Knowledge Sharing, Lessons from Systems Research

    CERN Document Server

    Di Maio, Paola

    2011-01-01

    The Open Access Movement has been striving to grant universal unrestricted access to the knowledge and data outputs of publicly funded research. leveraging the real time, virtually cost free publishing opportunities offered by the internet and the web. However, evidence suggests that in the systems engineering domain open access policies are not widely adopted. This paper presents the rationale, methodology and results of an evidence based inquiry that investigates the dichotomy between policy and practice in Open Access (OA) of systems engineering research in the UK, explores entangled dimensions of the problem space from a socio-technical perspective, and issues a set of recommendations, including a reference model outline for knowledge sharing in systems research

  18. Apartheid and healthcare access for paediatric systemic lupus ...

    African Journals Online (AJOL)

    lupus erythematosus (SLE), as a framework for evaluating the structural challenges to ... Paediatric SLE (pSLE) is more severe than the adult disease, and children with SLE .... exploration using a geographical information system. Soc Sci Med ...

  19. Micelles Based on Biodegradable Poly(L-glutamic acid)-b-Polylactide with Paramagnetic Gd Ions Chelated to the Shell Layer as a Potential Nanoscale MRI-Visible Delivery System

    Science.gov (United States)

    Zhang, Guodong; Zhang, Rui; Wen, Xiaoxia; Li, Li; Li, Chun

    2008-01-01

    There is much interest in the development of nanoscale drug delivery system with MRI visibility to optimize the delivery efficiency and therapeutic efficacy under image guidance. Here we report on the successful fabrication of nanoscale micelles based on biodegradable poly(L-glutamic acid)-b-polylactide (PG-b-PLA) block copolymer with paramagnetic Gd3+ ions chelated to their shell. (PG-b-PLA) was synthesized by sequential polymerization reactions: anionic polymerization of L-lactide followed by ring opening polymerization of benzyl glutamate N-carboxylic anhydride. The metal chelator p-aminobenzyldiethylenetriaminepenta(acetic acid) (DTPA) was readily conjugated to the side chain carboxylic acids of poly(L-glutamic acid). The resulting copolymer formed spherical micelles in aqueous solution with an average diameter of 230 nm at pH 7.4. The size of PG(DTPA)-b-PLA micelles decreased with increasing pH value. DTPA-Gd chelated to the shell layer of the micelles exhibited significantly higher spin-lattice relaxivity (r1) than a small-molecular-weight MRI contrast agent, indicating that water molecules could readily access the Gd ions in the micelles. Because of the presence of multiple carboxylic acid functional groups in the shell layer, polymeric micelles based on biodegradable PG(DTPA-Gd)-b-PLA may be a suitable platform for the development of MRI-visible, targeted nanoscale drug delivery systems. PMID:18047289

  20. What systems participants know about access and service entry and why managers should listen.

    Science.gov (United States)

    Duncombe, Rohena

    2016-08-29

    Objective The present study looked at the views of people directly involved in the entry process for community health counselling using the frame of the health access literature. The concurrence of system participants' views with the access literature highlights access issues, particularly for people who are vulnerable or disadvantaged. The paper privileges the voices of the system participants, inviting local health services to consider using participatory design to improve access at the entry point.Methods People involved in the entry process for community health counselling explored the question, 'What, for you, are the features of a good intake system?' They also commented on themes identified during pilot interviews. These were thematically analysed for each participant group by the researcher to develop a voice for each stakeholder group.Results People accessing the service could be vulnerable and the entry process failed to take that into account. People directly involved in the counselling service entry system, system participants, consisted of: professionals referring in, people seeking services and reception staff taking first enquiries. They shared substantially the same concerns as each other. The responses from these system participants are consistent with the international literature on access and entry into health services.Conclusion Participatory service design could improve primary healthcare service entry at the local level. Canvassing the experiences of system participants is important for delivering services to those who have the least access and, in that way, could contribute to health equity.What is known about the topic? People with the highest health needs receive the fewest services. Health inequality is increasing.What does this paper add? System participants can provide advice consistent with the academic research literature that is useful for improving service entry at the local level.What are the implications for practitioners

  1. A computer-aided detection system for rheumatoid arthritis MRI data interpretation and quantification of synovial activity

    Energy Technology Data Exchange (ETDEWEB)

    Kubassova, Olga, E-mail: olga@imageanalysis.org.u [Image Analysis Ltd., The Waterfront, Old Mill Lane, Saltaire BD17 7EZ (United Kingdom); Boesen, Mikael, E-mail: parker@frh.regionh.d [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark); Cimmino, Marco A., E-mail: cimmino@unige.i [Clinica Reumatologica, DI.M.I., Universita di Genova, Viale Benedetto XV, 6, 16129 Genova (Italy); Bliddal, Henning [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark)

    2010-06-15

    Rational and objective: Disease assessment and follow-up of rheumatoid arthritis (RA) patients require objective evaluation and quantification. Magnetic resonance imaging (MRI) has a large potential to supplement such information for the clinician, however, time spent on data reading and interpretation slow down development in this area. Existing scoring systems of especially synovitis are too rigid and insensitive to measure early treatment response and quantify inflammation. This study tested a novel automated, computer system for analysis of dynamic MRI data acquired from patients with RA, Dynamika-RA, which incorporates efficient data processing and analysis techniques. Materials and methods: 140 MRI scans from hands and wrists of 135 active RA patients and 5 healthy controls were processed using Dynamika-RA and evaluated with RAMRIS. To reduce patient motion artefacts, MRI data were processed using Dynamika-RA, which removed motion in 2D and 3D planes. Then synovial enhancement was visualised and qualified using a novel fully automated voxel-by-voxel analysis based algorithm. This algorithm was used to replace traditional region-of-interest (ROI) and subtraction methods, yielding observer independent quantitative results. Results: Conventional scoring performed by an observer took 30-45 min per dataset. Dynamika-RA reduced motion artefacts, visualised inflammation and quantified disease activity in less than 3 min. Data processing allowed increasing signal to noise ratio by a factor 3. Due to fully automated procedure of data processing, there was no intertest variation in the results. Conclusions: Algorithms incorporated into Dynamika-RA allow for the significant enhancement of data quality through eliminating motion artefacts and reduction of time for evaluation of synovial inflammation.

  2. A canine model of osteonecrosis of the femoral head induced by MRI guided argon helium cryotherapy system

    Science.gov (United States)

    Wang, Dong; Sun, Lixin; Zhang, Huawu; Jiang, Honglei; Liu, Ming; Tian, Jing; Hu, Na; Sun, Shui

    2015-01-01

    Objective: This study is to identify the reliability of osteonecrosis of the femoral head (ONFH) modeling established by MRI guided argon helium cryotherapy system in beagles. Methods: A total of 15 beagles were used to establish the ONFH model. The left femoral heads of the beagles received two cycles of argon helium freezing-thawing under MRI guidance and were considered as experimental group while the right femoral heads received only one cycle of argon helium freezing-thawing and were considered as the control group. X-ray, MRI, general shape and histological examinations were performed so as to identify the effect of modeling. Results: At 4 week after modeling, MRI showed obvious bilateral hip joint effusion and marked femoral head bone marrow high signal. At 8 week after surgery, abnormal signal appeared in bilateral femoral heads. T1WI showed irregular patchy low signal, T2WI showed irregular mixed signals and the joint capsule effusion showed long T1 and T2 changes. Twelve weeks after operation, T1WI showed a low signal strip with clear boundary and T2WI showed intermediate signal. The changes of the left femoral heads were significant while compared with those of the right sides. The lacunae rates of femoral heads in the experimental group at 4, 8, and 12 week after surgery (40.75 ± 3.77, 57.46 ± 4.01, 50.27 ± 2.98) were higher than those in control group (30.08 ± 3.61, 49.43 ± 2.82, 40.56 ± 2.73). Conclusion: Canine model of ONFH was successfully established using an argon helium cryotherapy system. PMID:26550205

  3. Principal component analysis of the dynamic response measured by fMRI: a generalized linear systems framework.

    Science.gov (United States)

    Andersen, A H; Gash, D M; Avison, M J

    1999-07-01

    Principal component analysis (PCA) is one of several structure-seeking multivariate statistical techniques, exploratory as well as inferential, that have been proposed recently for the characterization and detection of activation in both PET and fMRI time series data. In particular, PCA is data driven and does not assume that the neural or hemodynamic response reaches some steady state, nor does it involve correlation with any pre-defined or exogenous experimental design template. In this paper, we present a generalized linear systems framework for PCA based on the singular value decomposition (SVD) model for representation of spatio-temporal fMRI data sets. Statistical inference procedures for PCA, including point and interval estimation will be introduced without the constraint of explicit hypotheses about specific task-dependent effects. The principal eigenvectors capture both the spatial and temporal aspects of fMRI data in a progressive fashion; they are inherently matched to unique and uncorrelated features and are ranked in order of the amount of variance explained. PCA also acts as a variation reduction technique, relegating most of the random noise to the trailing components while collecting systematic structure into the leading ones. Features summarizing variability may not directly be those that are the most useful. Further analysis is facilitated through linear subspace methods involving PC rotation and strategies of projection pursuit utilizing a reduced, lower-dimensional natural basis representation that retains most of the information. These properties will be illustrated in the setting of dynamic time-series response data from fMRI experiments involving pharmacological stimulation of the dopaminergic nigro-striatal system in primates.

  4. Application of Attribute Based Access Control Model for Industrial Control Systems

    Directory of Open Access Journals (Sweden)

    Erkan Yalcinkaya

    2017-02-01

    Full Text Available The number of reported security vulnerabilities and incidents related to the industrial control systems (ICS has increased recent years. As argued by several researchers, authorization issues and poor access control are key incident vectors. The majority of ICS are not designed security in mind and they usually lack strong and granular access control mechanisms. The attribute based access control (ABAC model offers high authorization granularity, central administration of access policies with centrally consolidated and monitored logging properties. This research proposes to harness the ABAC model to address the present and future ICS access control challenges. The proposed solution is also implemented and rigorously tested to demonstrate the feasibility and viability of ABAC model for ICS.

  5. "MRI Stealth" robot for prostate interventions.

    Science.gov (United States)

    Stoianovici, Dan; Song, Danny; Petrisor, Doru; Ursu, Daniel; Mazilu, Dumitru; Muntener, Michael; Mutener, Michael; Schar, Michael; Patriciu, Alexandru

    2007-01-01

    The paper reports an important achievement in MRI instrumentation, a pneumatic, fully actuated robot located within the scanner alongside the patient and operating under remote control based on the images. Previous MRI robots commonly used piezoelectric actuation limiting their compatibility. Pneumatics is an ideal choice for MRI compatibility because it is decoupled from electromagnetism, but pneumatic actuators were hardly controllable. This achievement was possible due to a recent technology breakthrough, the invention of a new type of pneumatic motor, PneuStep 1, designed for the robot reported here with uncompromised MRI compatibility, high-precision, and medical safety. MrBot is one of the "MRI stealth" robots today (the second is described in this issue by Zangos et al.). Both of these systems are also multi-imager compatible, being able to operate with the imager of choice or cross-imaging modalities. For MRI compatibility the robot is exclusively constructed of nonmagnetic and dielectric materials such as plastics, ceramics, crystals, rubbers and is electricity free. Light-based encoding is used for feedback, so that all electric components are distally located outside the imager's room. MRI robots are modern, digital medical instruments in line with advanced imaging equipment and methods. These allow for accessing patients within closed bore scanners and performing interventions under direct (in scanner) imaging feedback. MRI robots could allow e.g. to biopsy small lesions imaged with cutting edge cancer imaging methods, or precisely deploy localized therapy at cancer foci. Our robot is the first to show the feasibility of fully automated in-scanner interventions. It is customized for the prostate and operates transperineally for needle interventions. It can accommodate various needle drivers for different percutaneous procedures such as biopsy, thermal ablations, or brachytherapy. The first needle driver is customized for fully automated low

  6. 5 CFR 293.504 - Composition of, and access to, the Employee Medical File System.

    Science.gov (United States)

    2010-01-01

    ... Employee Medical File System. 293.504 Section 293.504 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Employee Medical File System Records § 293.504 Composition of, and access to, the Employee Medical File System. (a) All employee occupational medical...

  7. China to Create an Access System for the Reproductive Health Industry Based on Quality Accreditation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Zhang Weiqing, director of the National Population and Family Planning Commission (NPFPC), disclosed at the inaugural meeting of the China Reproductive Health Industry Association (CRIA), held on March 26, 2007, that China will create an inspection system, a quality accreditation system, and an industry access system for better population structure and family planning.

  8. Measuring the Gap Between Car and Transit Accessibility : Estimating Access Using a High-Resolution Transit Network Geographic Information System

    NARCIS (Netherlands)

    Benenson, I.; Martens, C.J.C.M.; Rofé, Y.

    2010-01-01

    Accessibility is increasingly identified in the academic literature and in planning practice as a key criterion to assess transport policies and urban land use development. This paper contributes in two respects to the growing body of literature on accessibility and accessibility measurement. First,

  9. An open-source hardware and software system for acquisition and real-time processing of electrophysiology during high field MRI.

    Science.gov (United States)

    Purdon, Patrick L; Millan, Hernan; Fuller, Peter L; Bonmassar, Giorgio

    2008-11-15

    Simultaneous recording of electrophysiology and functional magnetic resonance imaging (fMRI) is a technique of growing importance in neuroscience. Rapidly evolving clinical and scientific requirements have created a need for hardware and software that can be customized for specific applications. Hardware may require customization to enable a variety of recording types (e.g., electroencephalogram, local field potentials, or multi-unit activity) while meeting the stringent and costly requirements of MRI safety and compatibility. Real-time signal processing tools are an enabling technology for studies of learning, attention, sleep, epilepsy, neurofeedback, and neuropharmacology, yet real-time signal processing tools are difficult to develop. We describe an open-source system for simultaneous electrophysiology and fMRI featuring low-noise (hardware distribution provides the complete specifications required to build an MRI-compatible electrophysiological data acquisition system, including circuit schematics, print circuit board (PCB) layouts, Gerber files for PCB fabrication and robotic assembly, a bill of materials with part numbers, data sheets, and vendor information, and test procedures. The software facilitates rapid implementation of real-time signal processing algorithms. This system has been used in human EEG/fMRI studies at 3 and 7T examining the auditory system, visual system, sleep physiology, and anesthesia, as well as in intracranial electrophysiological studies of the non-human primate visual system during 3T fMRI, and in human hyperbaric physiology studies at depths of up to 300 feet below sea level.

  10. Study of LANs access technologies in wind power system

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2010-01-01

    Due to the energy challenges in the world, new types of generation technologies, such as renewable energy based generators, attract great attention and are being quickly developed, which results in the dramatic developments and changes in modern power systems, the communication technologies play...... a increasingly important role in guaranteeing the power system’s stability, reliability, and security. In this paper the necessity of communication technologies employed in wind power system are introduced. According the International Standards Organization (ISO) reference 7-layered model, the communication...... power environment are explained and discussed. Furthermore the simulation of application of Ethernet in an offshore wind farm communication network by a software, OPNET, is elaborated. With the investigation of the communication technologies in this paper, the offshore wind farm SCADA system can...

  11. Access Control for Monitoring System-Spanning Business Processes

    NARCIS (Netherlands)

    Bassil, S.; Reichert, M.U.; Bobrik, R.; Bauer, Th.

    2007-01-01

    Integrated process support is highly desirable in environ- ments where data related to a particular (business) process are scattered over distributed and heterogeneous information systems (IS). A process monitoring component is a much-needed module in order to provide an integrated view on all these

  12. Labeling and Rating Systems: Greater Access or Censorship?

    Science.gov (United States)

    Martin, Ann M.

    2015-01-01

    This article asks the question: How well versed are school librarians on issues related to labeling and rating systems? As school librarians continue to design and implement resource location schemes to assist patrons, they must recognize the difference between using labels to create interest in books or implementing labeling and rating systems…

  13. Cognitive Spectrum Efficient Multiple Access Technique using Relay Systems

    DEFF Research Database (Denmark)

    Frederiksen, Flemming Bjerge; Prasad, Ramjee

    2007-01-01

    Methods to enhance the use of the frequency spectrum by automatical spectrum sensing plus spectrum sharing in a cognitive radio technology context will be presented and discussed in this paper. Ideas to increase the coverage of cellular systems by relay channels, relay stations and collaborate ra...

  14. Cognitive Spectrum Efficient Multiple Access Technique using Relay Systems

    DEFF Research Database (Denmark)

    Frederiksen, Flemming Bjerge; Prasad, Ramjee

    2007-01-01

    Methods to enhance the use of the frequency spectrum by automatical spectrum sensing plus spectrum sharing in a cognitive radio technology context will be presented and discussed in this paper. Ideas to increase the coverage of cellular systems by relay channels, relay stations and collaborate...

  15. Neural systems for social cognition in Klinefelter syndrome (47.XXY) : evidence from fMRI

    NARCIS (Netherlands)

    van Rijn, S.; Swaab, H; Baas, D; de Haan, E; Kahn, R.S.; Aleman, A.

    2012-01-01

    Klinefelter syndrome (KS) is a chromosomal condition (47, XXY) that may help us to unravel gene-brain behavior pathways to psychopathology. The phenotype includes social cognitive impairments and increased risk for autism traits. We used functional MRI to study neural mechanisms underlying social in

  16. Quantitative Clinical Evaluation of a Simultaneous PETI MRI Breast Imaging System

    Energy Technology Data Exchange (ETDEWEB)

    Schlyer D. J.; Schlyer, D.J.

    2013-04-03

    A prototype simultaneous PET-MRI breast scanner has been developed for conducting clinical studies with the goal of obtaining high resolution anatomical and functional information in the same scan which can lead to faster and better diagnosis, reduction of unwanted biopsies, and better patient care.

  17. Auditory Verb Perception Recruits Motor Systems in the Developing Brain: An fMRI Investigation

    Science.gov (United States)

    James, Karin Harman; Maouene, Josita

    2009-01-01

    This study investigated neural activation patterns during verb processing in children, using fMRI (functional Magnetic Resonance Imaging). Preschool children (aged 4-6) passively listened to lists of verbs and adjectives while neural activation was measured. Findings indicated that verbs were processed differently than adjectives, as the verbs…

  18. Computer-assisted three-dimensional reconstruction of the corticospinal system as a reference for CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Buhmann, C. [Department of Neuroanatomy, Hannover Medical School (Germany)]|[University Hospital Eppendorf, Hamburg (Germany); Kretschmann, H.J. [Department of Neuroanatomy, Hannover Medical School (Germany)

    1998-09-01

    We present a three-dimensional (3D) anatomical computer-graphics model of the corticospinal system acquired from equidistant serial anatomical slices of six intracranially-fixed human brains. This model is part of a neuroanatomical reference system (NeuRef) which enables 3D visualization of the brain and shows the relationship of its components such as anatomical structures, functional fibre tracts and arteries. Sections through the models can be matched with corresponding CT or MR images. This allows the probable localisation of corticospinal fibres on CT or MRI. (orig.) (orig.) With 18 figs., 3 tabs., 40 refs.

  19. Scheduling with Bus Access Optimization for Distributed Embedded Systems

    DEFF Research Database (Denmark)

    Eles, Petru; Doboli, Alex; Pop, Paul;

    2000-01-01

    In this paper, we concentrate on aspects related to the synthesis of distributed embedded systems consisting of programmable processors and application-specific hardware components. The approach is based on an abstract graph representation that captures, at process level, both dataflow and the flow...... of control. Our goal is to derive a worst case delay by which the system completes execution, such that this delay is as small as possible; to generate a logically and temporally deterministic schedule; and to optimize parameters of the communication protocol such that this delay is guaranteed. We have...... have to be considered during scheduling but also the parameters of the communication protocol should be adapted to fit the particular embedded application. The optimization algorithm, which implies both process scheduling and optimization of the parameters related to the communication protocol...

  20. Multi-tag content access control in RFID system

    OpenAIRE

    2010-01-01

    Radio Frequency Identification (RFID) makes great flexibility and high efficiency for data acquisition in industry and daily life. At the other side, it brings the privacy risks and multiple tags collision issue. Current research in RFID system focuses on the security and privacy issue which is based on authentication protocols between a tag and a Reader. There is a need to design a reasonable protocol which takes care of both multi-tag anti-collision and security issue. This thesis presen...

  1. Scheduling of network access for feedback-based embedded systems

    Science.gov (United States)

    Liberatore, Vincenzo

    2002-07-01

    nd communication capabilities. Examples range from smart dust embedded in building materials to networks of appliances in the home. Embedded devices will be deployed in unprecedented numbers, will enable pervasive distributed computing, and will radically change the way people interact with the surrounding environment [EGH00a]. The paper targets embedded systems and their real-time (RT) communication requirements. RT requirements arise from the

  2. Generation-based memory synchronization in a multiprocessor system with weakly consistent memory accesses

    Science.gov (United States)

    Ohmacht, Martin

    2014-09-09

    In a multiprocessor system, a central memory synchronization module coordinates memory synchronization requests responsive to memory access requests in flight, a generation counter, and a reclaim pointer. The central module communicates via point-to-point communication. The module includes a global OR reduce tree for each memory access requesting device, for detecting memory access requests in flight. An interface unit is implemented associated with each processor requesting synchronization. The interface unit includes multiple generation completion detectors. The generation count and reclaim pointer do not pass one another.

  3. Generation-based memory synchronization in a multiprocessor system with weakly consistent memory accesses

    Energy Technology Data Exchange (ETDEWEB)

    Ohmacht, Martin

    2017-08-15

    In a multiprocessor system, a central memory synchronization module coordinates memory synchronization requests responsive to memory access requests in flight, a generation counter, and a reclaim pointer. The central module communicates via point-to-point communication. The module includes a global OR reduce tree for each memory access requesting device, for detecting memory access requests in flight. An interface unit is implemented associated with each processor requesting synchronization. The interface unit includes multiple generation completion detectors. The generation count and reclaim pointer do not pass one another.

  4. Clinico-MRI study of hemispheric disorder in long-term follow-up cases of multiple system atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Konagaya, Masaaki; Miwa, Shigeru; Matsuoka, Yukihiko [Suzuka National Hospital, Mie (Japan); Konagaya, Yoko

    1998-12-01

    Twelve cases of multiple system atrophy (MSA) were studied for clinical and MRI findings of the cerebral hemispheric involvement. The subjects consisted of five olivopontocerebellar atrophy (OPCA) type and seven striatonigral degeneration (SND) type. The age at onset was 56.7{+-}8.0 (M{+-}SD) years, duration of illness at the first MRI study 3.2{+-}1.1 years, duration of illness at the last study 8.1{+-}2.2 years, and the following up duration 4.9{+-}2.0 years. The grasping phenomenon was observed in 70% of the cases examined, snout reflex in 80%, slowness of verbal response in 88%, and decrease of spontaneous speech in 100%. Three cases finally fell into the state of mutism. Three out of ten cases were categorized as dementia by HDS-R (Hasegawa Dementia Scale-Revised) test. Besides the progression of the pontocerebellar atrophy and putaminal changes, MRI study revealed progressive frontal lobe atrophy in most cases. At six years after the onset, SND type showed significantly higher incidence of conspicuous frontal lobe atrophy and dilatation of the Sylvian fissure than OPCA type. Cerebral ventricular dilatation was common feature, and atrophy of the temporal and occipital lobes were observed in several cases. We indicated the possible involvement of the cerebral hemisphere, especially the frontal lobe, and higher nervous function in MSA. (author)

  5. Geoculture world system, access to Balkan and Albania

    Directory of Open Access Journals (Sweden)

    Ilirjan Çukaj

    2015-03-01

    Full Text Available If culture as a term covers a broad range of relations and social behavior, mutually implicated in influential and economic cycles of the global system, then it becomes wordy geoculture. Geoculture system is used as a term by Wallerstein (2004 who had treated it as a concept largely unused and under a theory of geoculture which plays an important role in the present world system. The theses that is presented in this article is that the global trajectory in the Balkan region is increasing from culture and that, it is imperative to establish a strategic culture direction and management, which, in turn, should be formed not only as a principal need, but also as an obligation of social state institutions to find the viable solutions of the global market policy, economy and culture. And in response to the challenging question the culture of integration becomes imperative now facing nationalism. Albania will have to manage perceptions, fears and realities arising from the above mentioned phenomenon, to establish a balance between the “inside” and “outside” views. In this sense main challenge of Albania is the management of cultural globalization to get the most of opportunities despite the risk of losing ground globally

  6. Evaluation of the incidence of nephrogenic systemic fibrosis in patients with moderate renal insufficiency administered gadobenate dimeglumine for MRI

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, B.J. [Department of Radiology, Loma Linda University Medical Center, Loma Linda, California (United States)], E-mail: BJBryant@ahs.llumc.edu; Im, K.; Broome, D.R. [Department of Radiology, Loma Linda University Medical Center, Loma Linda, California (United States)

    2009-07-15

    Aim: To determine the incidence of nephrogenic systemic fibrosis (NSF) in stage 3 chronic kidney disease patients following intravenous exposure to gadobenate dimeglumine. Materials and methods: A prospective study was performed on 168 consecutive patients at a single institution with stage 3 chronic kidney disease who underwent clinically-indicated contrast-enhanced magnetic resonance imaging (MRI) examinations with gadobenate dimeglumine from January 2007 to March 2008. All patients were contacted by phone by investigators 3 months after MRI to verify the presence or absence of NSF signs or symptoms. If signs or symptoms suggestive of NSF developed, dermatologic referral was made and confirmatory skin biopsy performed if indicated. Results: One hundred and eighty contrast-enhanced MRI examinations with gadobenate dimeglumine were performed on the 168 patients. Twenty patients were lost to follow-up, but 160 incidents of contrast medium exposure were followed up for 3-months and 105 incidents were followed up for 6 months. The mean contrast medium dose per weight was 0.093 mmol/kg (range 0.042-0.153 mmol/kg). The mean estimated creatinine clearance was 50.4 ml/min/1.73 m{sup 2} (range from 30-59 ml/min/1.73 m{sup 2}). Ten patients developed skin rashes during the 3-month follow-up period, but none were confirmed to represent NSF (0% prevalence rate). No other signs or symptoms of NSF were reported. Conclusion: Based on this limited study, NSF does not appear to occur in patients with stage 3 chronic kidney disease exposed to intravenous gadobenate dimeglumine for MRI at standard dosing of {approx}0.1 mmol/kg.

  7. Design and Implementation of a Library and Information Science Open Access Journal Union Catalogue System

    Directory of Open Access Journals (Sweden)

    Sinn-Cheng Lin

    2017-03-01

    Full Text Available Open access is a mode of academic communication that has been on the rise in recent years, but open access academic resources are widely dispersed across the internet, making it occasionally inconvenient in terms of its use. This research is focused on library and information science, using the OAIS reference model as the system framework, two open access platform, DOAJ and E-LIS as the data sources, and through system implementation develop a “library and information science open access journal union catalogue” system. Using the OAI-PMH protocol as the data interoperability standard, and LAMP as the development environment, four major functionalities: injest, archiving, management and access of information were designed, developed, and integrated into system build. Actual testing and verification showed this system is able to successfully collect data from DOAJ and E-LIS open journal resources related to library and information science. The system is now active and functional, and can be used by researchers in the library and science information field.

  8. Bus Access Optimization for Distributed Embedded Systems Based on Schedulability Analysis

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    2000-01-01

    We present an approach to bus access optimization and schedulability analysis for the synthesis of hard real-time distribution embedded systems. The communication model is based on a time-triggered protocol. We have developed an analysis for the communication delays proposing four different message...... scheduling policies over a time-triggered communication channel. Optimization strategies for the bus access scheme are developed, and the four approaches to message scheduling are compared using extensive experiments....

  9. Security Guidelines for the Development of Accessible Web Applications through the implementation of intelligent systems

    Directory of Open Access Journals (Sweden)

    Luis Joyanes Aguilar

    2009-12-01

    Full Text Available Due to the significant increase in threats, attacks and vulnerabilities that affect the Web in recent years has resulted the development and implementation of pools and methods to ensure security measures in the privacy, confidentiality and data integrity of users and businesses. Under certain circumstances, despite the implementation of these tools do not always get the flow of information which is passed in a secure manner. Many of these security tools and methods cannot be accessed by people who have disabilities or assistive technologies which enable people to access the Web efficiently. Among these security tools that are not accessible are the virtual keyboard, the CAPTCHA and other technologies that help to some extent to ensure safety on the Internet and are used in certain measures to combat malicious code and attacks that have been increased in recent times on the Web. Through the implementation of intelligent systems can detect, recover and receive information on the characteristics and properties of the different tools and hardware devices or software with which the user is accessing a web application and through analysis and interpretation of these intelligent systems can infer and automatically adjust the characteristics necessary to have these tools to be accessible by anyone regardless of disability or navigation context. This paper defines a set of guidelines and specific features that should have the security tools and methods to ensure the Web accessibility through the implementation of intelligent systems.

  10. Co-Registration of MEG and ULF MRI using a 7 channel low-Tc SQUID system

    Energy Technology Data Exchange (ETDEWEB)

    Magnelind, Per E [Los Alamos National Laboratory; Sandin, Jan H [Los Alamos National Laboratory; Volegov, Petr L [Los Alamos National Laboratory; Matlashov, Andrei N [Los Alamos National Laboratory; Owens, Tuba [Los Alamos National Laboratory; Gomez, John J [Los Alamos National Laboratory; Espy, Michelle A [Los Alamos National Laboratory

    2010-01-01

    In human brain imaging, e.g. pre-surgical mapping, it is highly desired to obtain images with high spatial and temporal resolution. However, no single imaging device is capable of producing both a high spatial resolution anatomical image and a high temporal resolution functional image. During the last couple of years significant efforts have been directed towards magnetic resonance imaging (MRI) in fields comparable to the Earth's field, i.e. microtesla fields, or lower fields. The fields in this range are called ultra-low fields (ULF). Interestingly, the idea of magnetic resonance at microtesla fields is more than 50 years old. In ULF MR it is essential to use pre-polarization to increase the signal-to-noise ratio of the signal from the precessing spins, since the magnetization from the measurement field alone is very small. Even with the present level of prepolarization the ULF images are not as highly resolved as their high-field counterparts. By using a 7 channel system equipped with low transition temperature (T{sub c}) Superconducting QUantum Interference Devices (SQUIDs) to perform both ULF MRI and magnetoencephalography (MEG), it is possible to coregister a lower resolution ULF MR image and an MEG image obtained during one run. Thereby, the MEG data is aligned to the ULF MR image after performing a calibration run with a phantom. The ULF MR image can then be used to align the MEG data onto a high-field MR image. Recently, our group presented the first brain images obtained by ULF MRI. The MR imaging was combined with an MEG session performed a posteriori. The subject's head was moved in between the MRI run and the MEG run and no reference coils were used to quantify the translation. The main reason for the translation of the head was to improve the coverage of the auditory evoked response. In this paper, we report interleaved ULF MRI and MEG measurements co-registered in the same system.

  11. Design of pulse waveform for waveform division multiple access UWB wireless communication system.

    Science.gov (United States)

    Yin, Zhendong; Wang, Zhirui; Liu, Xiaohui; Wu, Zhilu

    2014-01-01

    A new multiple access scheme, Waveform Division Multiple Access (WDMA) based on the orthogonal wavelet function, is presented. After studying the correlation properties of different categories of single wavelet functions, the one with the best correlation property will be chosen as the foundation for combined waveform. In the communication system, each user is assigned to different combined orthogonal waveform. Demonstrated by simulation, combined waveform is more suitable than single wavelet function to be a communication medium in WDMA system. Due to the excellent orthogonality, the bit error rate (BER) of multiuser with combined waveforms is so close to that of single user in a synchronous system. That is to say, the multiple access interference (MAI) is almost eliminated. Furthermore, even in an asynchronous system without multiuser detection after matched filters, the result is still pretty ideal and satisfactory by using the third combination mode that will be mentioned in the study.

  12. Cognitive radio networks medium access control for coexistence of wireless systems

    CERN Document Server

    Bian, Kaigui; Gao, Bo

    2014-01-01

    This book gives a comprehensive overview of the medium access control (MAC) principles in cognitive radio networks, with a specific focus on how such MAC principles enable different wireless systems to coexist in the same spectrum band and carry out spectrum sharing.  From algorithm design to the latest developments in the standards and spectrum policy, readers will benefit from leading-edge knowledge of how cognitive radio systems coexist and share spectrum resources.  Coverage includes cognitive radio rendezvous, spectrum sharing, channel allocation, coexistence in TV white space, and coexistence of heterogeneous wireless systems.   • Provides a comprehensive reference on medium access control (MAC)-related problems in the design of cognitive radio systems and networks; • Includes detailed analysis of various coexistence problems related to medium access control in cognitive radio networks; • Reveals novel techniques for addressing the challenges of coexistence protocol design at a higher level ...

  13. A Distributed Metadata Management, Data Discovery and Access System

    CERN Document Server

    Palanisamy, Giriprakash; Green, Jim; Wilson, Bruce

    2010-01-01

    Mercury is a federated metadata harvesting, search and retrieval tool based on both open source and software developed at Oak Ridge National Laboratory. It was originally developed for NASA, and the Mercury development consortium now includes funding from NASA, USGS, and DOE. A major new version of Mercury was developed during 2007. This new version provides orders of magnitude improvements in search speed, support for additional metadata formats, integration with Google Maps for spatial queries, support for RSS delivery of search results, among other features. Mercury provides a single portal to information contained in disparate data management systems. It collects metadata and key data from contributing project servers distributed around the world and builds a centralized index. The Mercury search interfaces then allow the users to perform simple, fielded, spatial and temporal searches across these metadata sources. This centralized repository of metadata with distributed data sources provides extremely fa...

  14. Estimation of minimum miscibility pressure (MMP) of CO2 and liquid n-alkane systems using an improved MRI technique.

    Science.gov (United States)

    Liu, Yu; Jiang, Lanlan; Song, Yongchen; Zhao, Yuechao; Zhang, Yi; Wang, Dayong

    2016-02-01

    Minimum miscible pressure (MMP) of gas and oil system is a key parameter for the injection system design of CO2 miscible flooding. Some industrial standard approaches such as the experiment using a rising bubble apparatus (RBA), the slim tube tests (STT), the pressure-density diagram (PDD), etc. have been applied for decades to determine the MMP of gas and oil. Some theoretical or experiential calculations of the MMP were also applied to the gas-oil miscible system. In the present work, an improved technique based on our previous research for the estimation of the MMP by using magnetic resonance imaging (MRI) was proposed. This technique was then applied to the CO2 and n-alkane binary and ternary systems to observe the mixing procedure and to study the miscibility. MRI signal intensities, which represent the proton concentration of n-alkane in both the hydrocarbon rich phase and the CO2 rich phase, were plotted as a reference for determining the MMP. The accuracy of the MMP obtained by using this improved technique was enhanced comparing with the data obtained from our previous works. The results also show good agreement with other established techniques (such as the STT) in previous published works. It demonstrates increases of MMPs as the temperature rise from 20 °C to 37.8 °C. The MMPs of CO2 and n-alkane systems are also found to be proportional to the carbon number in the range of C10 to C14.

  15. An Information System to Access Status Information of the LHCb Online

    Science.gov (United States)

    Frank, M.; Gaspar, C.

    2012-12-01

    The LHCb collaboration consists of roughly 700 physicists from 52 institutes and universities. Most of the collaborating physicists - including subdetector experts - are not permanently based at CERN. This paper describes the architecture used to publish data internal to the LHCb experiment control- and data acquisition system to the World Wide Web. Collaborators can access the online (sub-) system status and the system performance directly from the institute abroad, from home or from a smart phone without the need of direct access to the online computing infrastructure.

  16. Rules and access rights of the Estonian integrated e-Health system.

    Science.gov (United States)

    Tiik, Madis

    2010-01-01

    There should be a clear understanding that when implementing an electronic health record system (EHR), one of the hardest problems we have to solve is the access rights. In Estonia this process lasted for three years and involved all stakeholders of the healthcare sector. Special ethical committee was established to advise the decision makers and doctors to help them understand the ethical dilemmas from the patient's and society's point of view. In this article you will find a short overview of the access rights of the system, roles of the healthcare systems' employees. Descriptions of some specific situations like underage patients and representation of patient with restricted active legal capacity.

  17. Intraoperative MRI in pediatric brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Choudhri, Asim F. [Le Bonheur Children' s Hospital, Department of Radiology, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Neurosurgery, Memphis, TN (United States); University of Tennessee Health Science Center, Department of Ophthalmology, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States); Siddiqui, Adeel [University of Tennessee Health Science Center, Department of Radiology, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States); Klimo, Paul; Boop, Frederick A. [University of Tennessee Health Science Center, Department of Neurosurgery, Memphis, TN (United States); Le Bonheur Children' s Hospital, Le Bonheur Neuroscience Institute, Memphis, TN (United States); Semmes-Murphey Neurologic and Spine Institute, Memphis, TN (United States); St. Jude Children' s Hospital, Division of Neurosurgery, Department of Surgery, Memphis, TN (United States)

    2015-09-15

    Intraoperative magnetic resonance imaging (iMRI) has emerged as an important tool in guiding the surgical management of children with brain tumors. Recent advances have allowed utilization of high field strength systems, including 3-tesla MRI, resulting in diagnostic-quality scans that can be performed while the child is on the operating table. By providing information about the possible presence of residual tumor, it allows the neurosurgeon to both identify and resect any remaining tumor that is thought to be safely accessible. By fusing the newly obtained images with the surgical guidance software, the images have the added value of aiding in navigation to any residual tumor. This is important because parenchyma often shifts during surgery. It also gives the neurosurgeon insight into whether any immediate postoperative complications have occurred. If any complications have occurred, the child is already in the operating room and precious minutes lost in transport and communications are saved. In this article we review the three main approaches to an iMRI system design. We discuss the possible roles for iMRI during intraoperative planning and provide guidance to help radiologists and neurosurgeons alike in the collaborative management of these children. (orig.)

  18. Access to essential medicines in Pakistan: policy and health systems research concerns.

    Directory of Open Access Journals (Sweden)

    Shehla Zaidi

    Full Text Available INTRODUCTION: Inadequate access to essential medicines is a common issue within developing countries. Policy response is constrained, amongst other factors, by a dearth of in-depth country level evidence. We share here i gaps related to access to essential medicine in Pakistan; and ii prioritization of emerging policy and research concerns. METHODS: An exploratory research was carried out using a health systems perspective and applying the WHO Framework for Equitable Access to Essential Medicine. Methods involved key informant interviews with policy makers, providers, industry, NGOs, experts and development partners, review of published and grey literature, and consultative prioritization in stakeholder's Roundtable. FINDINGS: A synthesis of evidence found major gaps in essential medicine access in Pakistan driven by weaknesses in the health care system as well as weak pharmaceutical regulation. 7 major policy concerns and 11 emerging research concerns were identified through consultative Roundtable. These related to weaknesses in medicine registration and quality assurance systems, unclear and counterproductive pricing policies, irrational prescribing and sub-optimal drug availability. Available research, both locally and globally, fails to target most of the identified policy concerns, tending to concentrate on irrational prescriptions. It overlooks trans-disciplinary areas of policy effectiveness surveillance, consumer behavior, operational pilots and pricing interventions review. CONCLUSION: Experience from Pakistan shows that policy concerns related to essential medicine access need integrated responses across various components of the health systems, are poorly addressed by existing evidence, and require an expanded health systems research agenda.

  19. Diagnostic accuracy of a five-point Likert scoring system for magnetic resonance imaging (MRI) evaluated according to results of MRI/ultrasonography image-fusion targeted biopsy of the prostate.

    Science.gov (United States)

    Shin, Toshitaka; Smyth, Thomas B; Ukimura, Osamu; Ahmadi, Nariman; de Castro Abreu, Andre Luis; Ohe, Chisato; Oishi, Masakatsu; Mimata, Hiromitsu; Gill, Inderbir S

    2017-07-27

    To evaluate the accuracy of a magnetic resonance imaging (MRI)-based Likert scoring system in the detection of clinically significant prostate cancer (CSPC), using MRI/ultrasonography (US) image-fusion targeted biopsy (FTB) as a reference standard. We retrospectively reviewed 1218 MRI-detected lesions in 629 patients who underwent subsequent MRI/US FTB between October 2012 and August 2015. 3-Tesla MRI was independently reported by one of eight radiologists with varying levels of experience and scored on a five-point Likert scale. All lesions with Likert scores 1-5 were prospectively defined as targets for MRI/US FTB. CSPC was defined as Gleason score ≥7. The median patient age was 64 years, PSA level 6.97 ng/mL and estimated prostate volume 52.2 mL. Of 1218 lesions, 48% (n = 581) were rated as Likert 1-2, 35% (n = 428) were Likert 3 and 17% (n = 209) were Likert 4-5. For Likert scores 1-5, the overall cancer detection rates were 12%, 13%, 22%, 50% and 59%, respectively, and the CSPC detection rates were 4%, 4%, 12%, 33% and 48%, respectively. Grading using the five-point scale showed strong positive correlation with overall cancer detection rate (r = 0.949, P = 0.05) and CSPC detection rate (r = 0.944, P = 0.05). By comparison, in Likert 4-5 lesions, significant differences were noted in overall cancer detection rate (63% vs 35%; P = 0.001) and CSPC detection rate (47% vs 29%; P = 0.027) for the more experienced vs the less experienced radiologists. The detection rates of overall cancer and CSPC strongly correlated with the five-point grading of the Likert scale. Among radiologists with different levels of experience, there were significant differences in these cancer detection rates. © 2017 The Authors BJU International © 2017 BJU International Published by John Wiley & Sons Ltd.

  20. 28 CFR 16.99 - Exemption of the Immigration and Naturalization Service Systems-limited access.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Exemption of the Immigration and....99 Exemption of the Immigration and Naturalization Service Systems-limited access. (a) The following systems of records of the Immigration and Naturalization Service are exempt from 5 U.S.C. 552a (c) (3)...

  1. Experimental grid access for dynamic discovery and data transfer in distributed interactive simulation systems

    NARCIS (Netherlands)

    A. Tirado-Ramos; K. Zajac; Z. Zhao; P.M.A. Sloot; G.D. van Albada; M. Bubak

    2003-01-01

    Interactive Problem Solving Environments (PSEs) offer an integrated approach for constructing and running complex systems, such as distributed simulation systems. New distributed infrastructures, like the Grid, support the access to a large variety of core services and resources that can be used by

  2. Bus Access Optimisation for FlexRay-based Distributed Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Traian; Pop, Paul; Eles, Petru

    2007-01-01

    -real time communication in a deterministic manner. In this paper, we propose techniques for optimising the FlexRay bus access mechanism of a distributed system, so that the hard real-time deadlines are met for all the tasks and messages in the system. We have evaluated the proposed techniques using...

  3. Multi-level access control in the data pipeline of the international supply chain system

    NARCIS (Netherlands)

    Pruksasri, P.; Berg, J. van den; Hofman, W.; Daskapan, S.

    2013-01-01

    The Seamless Integrated Data Pipeline system was proposed to the European Union in order to overcome the information quality shortcomings of the current international supply chain information exchange systems. Next to identification and authorization of stakeholders, secure access control needs to b

  4. Environmental Information Management For Data Discovery and Access System

    Science.gov (United States)

    Giriprakash, P.

    2011-01-01

    Mercury is a federated metadata harvesting, search and retrieval tool based on both open source software and software developed at Oak Ridge National Laboratory. It was originally developed for NASA, and the Mercury development consortium now includes funding from NASA, USGS, and DOE. A major new version of Mercury was developed during 2007 and released in early 2008. This new version provides orders of magnitude improvements in search speed, support for additional metadata formats, integration with Google Maps for spatial queries, support for RSS delivery of search results, and ready customization to meet the needs of the multiple projects which use Mercury. For the end users, Mercury provides a single portal to very quickly search for data and information contained in disparate data management systems. It collects metadata and key data from contributing project servers distributed around the world and builds a centralized index. The Mercury search interfaces then allow ! the users to perform simple, fielded, spatial and temporal searches across these metadata sources. This centralized repository of metadata with distributed data sources provides extremely fast search results to the user, while allowing data providers to advertise the availability of their data and maintain complete control and ownership of that data.

  5. A High Speed Mobile Courier Data Access System That Processes Database Queries in Real-Time

    Science.gov (United States)

    Gatsheni, Barnabas Ndlovu; Mabizela, Zwelakhe

    A secure high-speed query processing mobile courier data access (MCDA) system for a Courier Company has been developed. This system uses the wireless networks in combination with wired networks for updating a live database at the courier centre in real-time by an offsite worker (the Courier). The system is protected by VPN based on IPsec. There is no system that we know of to date that performs the task for the courier as proposed in this paper.

  6. SU-E-J-205: Dose Distribution Differences Caused by System Related Geometric Distortion in MRI-Guided Radiation Treatment System

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J; Yang, J; Wen, Z [MD Anderson Cancer Center, Houston, TX (United States); Marshall, S [Monaco, Elekta AB, Tampa, FL (Monaco); Court, L; Ibbott, G [UT MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: MRI has superb soft tissue contrast but is also known for geometric distortions. The concerns and uncertainty about MRI’s geometric distortion have contributed to the hesitation of using only MRI for simulation in radiation therapy. There are two major categories of geometric distortion in MRI; system related and patient related. In this presentation, we studied the impact of system-related geometric distortion on dose distribution in a digital body phantom under an MR-Linac environment. Methods: Residual geometric distortion (after built-in geometric correction) was modeled based on phantom measurements of the system-related geometric distortions of a MRI scanner of a combined MR guided Radiation Therapy (MRgRT) system. A digital oval shaped phantom (40×25 cm) as well as one ellipsoid shaped tumor volume was created to simulate a simplified human body. The simulated tumor volume was positioned at several locations between the isocenter and the body surface. CT numbers in HUs that approximate soft tissue and tumor were assigned to the respective regions in the digital phantom. To study the effect of geometric distortion caused by system imperfections, an IMRT plan was optimized with the distorted image set with the B field. Dose distributions were re-calculated on the undistorted image set with the B field (as in MR-Linac). Results: The maximum discrepancies in both body contour and tumor boundary was less than 2 mm, which leads to small dose distribution change. For the target in the center, coverage was reduced from 98.8% (with distortion) to 98.2%; for the other peripheral target coverage was reduced from 98.4% to 95.9%. Conclusion: System related geometric distortions over the 40×25 area were within 2mm and the resulted dosimetric effects were minor for the two tumor locations in the phantom. Patient study will be needed for further investigation. The authors received a corporate research grant from Elekta.

  7. Central nervous system infectious diseases mimicking multiple sclerosis: recognizing distinguishable features using MRI

    Directory of Open Access Journals (Sweden)

    Antonio Jose da Rocha

    2013-09-01

    Full Text Available The current diagnostic criteria for multiple sclerosis (MS confirm the relevant role of magnetic resonance imaging (MRI, supporting the possibility of characterizing the dissemination in space (DIS and the dissemination in time (DIT in a single scan. To maintain the specificity of these criteria, it is necessary to determine whether T2/FLAIR visible lesions and the gadolinium enhancement can be attributed to diseases that mimic MS. Several diseases are included in the MS differential diagnosis list, including diseases with exacerbation, remitting periods and numerous treatable infectious diseases, which can mimic the MRI features of MS. We discuss the most relevant imaging features in several infectious diseases that resemble MS and examine the primary spatial distributions of lesions and the gadolinium enhancement patterns related to MS. Recognizing imaging "red flags" can be useful for the proper diagnostic evaluation of suspected cases of MS, facilitating the correct differential diagnosis by assessing the combined clinical, laboratory and MR imaging information.

  8. Gradiometer Using Middle Loops as Sensing Elements in a Low-Field SQUID MRI System

    Science.gov (United States)

    Penanen, Konstantin; Hahn, Inseob; Ho Eom, Byeong

    2009-01-01

    A new gradiometer scheme uses middle loops as sensing elements in lowfield superconducting quantum interference device (SQUID) magnetic resonance imaging (MRI). This design of a second order gradiometer increases its sensitivity and makes it more uniform, compared to the conventional side loop sensing scheme with a comparable matching SQUID. The space between the two middle loops becomes the imaging volume with the enclosing cryostat built accordingly.

  9. Area summation in human visual system: psychophysics, fMRI, and modeling.

    Science.gov (United States)

    Nurminen, Lauri; Kilpeläinen, Markku; Laurinen, Pentti; Vanni, Simo

    2009-11-01

    Contextual modulation is a fundamental feature of sensory processing, both on perceptual and on single-neuron level. When the diameter of a visual stimulus is increased, the firing rate of a cell typically first increases (summation field) and then decreases (surround field). Such an area summation function draws a comprehensive profile of the receptive field structure of a neuron, including areas outside the classical receptive field. We investigated area summation in human vision with psychophysics and functional magnetic resonance imaging (fMRI). The stimuli were drifting sine wave gratings similar to those used in previous macaque single-cell area summation studies [corrected]. A model was developed to facilitate comparison of area summation in fMRI to area summation in psychophysics and single cells. The model consisted of units with an antagonistic receptive field structure found in single cells in the primary visual cortex. The receptive field centers of the model neurons were distributed in the region of the visual field covered by a single voxel. The measured area summation functions were qualitatively similar to earlier single-cell data. The model with parameters derived from psychophysics captured the spatial structure of the summation field in the primary visual cortex as measured with fMRI. The model also generalized to a novel situation in which the neural population was displaced from the stimulus center. The current study shows that contextual modulation arises from similar spatially antagonistic and overlapping excitatory and inhibitory mechanisms, both in single cells and in human vision.

  10. A test bed for the future access control system the AD Project

    CERN Document Server

    Scibile, L

    1999-01-01

    This paper describes the design, management and development of the new access control system for the Antiproton Deceleration experimental area, called the AD Project. As this project includes all the elements for the industrial evolution of the present access control system it is an ideal test bed for future access systems. The adoption of new technologies and techniques are described, and the benefits and the shortfalls are highlighted. The open redundant architecture solution, based on a PROFIBUS network and standard industrial components (HP-UNIX, Siemens S7 PLC, Siemens Industrial PC, door locks), guarantees reliability, safety and optimal integration. The project team took advantage of the Goal Directed Project Management technique and managed to define a clear and effective strategy.

  11. Accessing Multi-Source Geological Data through Network in MORPAS Software System

    Institute of Scientific and Technical Information of China (English)

    Mei Hongbo; Hu Guangdao; Chen Jianguo; Li Zhenhua

    2003-01-01

    MORPAS is a special GIS (geographic information system) software system, based on the MAPGIS platform whose aim is to prospect and evaluate mineral resources quantificationally by synthesizing geological, geophysical, geochemical and remote sensing data. It overlays geological database management, geological background and geological abnormality analysis, image processing of remote sensing and comprehensive abnormality analysis, etc.. It puts forward an integrative solution for the application of GIS in basic-level units and the construction of information engineering in the geological field. As the popularization of computer networks and the request of data sharing, it is necessary to extend its functions in data management so that all its data files can be accessed in the network server. This paper utilizes some MAPGIS functions for the second development and ADO (access data object) technique to access multi-source geological data in SQL Server databases. Then remote visiting and congruous management will be realized in the MORPAS system.

  12. A CAD system based on multi-parametric analysis for cancer prostate detection on DCE-MRI

    Science.gov (United States)

    Mazzetti, Simone; De Luca, Massimo; Bracco, Christian; Vignati, Anna; Giannini, Valentina; Stasi, Michele; Russo, Filippo; Armando, Enrico; Agliozzo, Silvano; Regge, Daniele

    2011-03-01

    Computer-aided diagnosis (CAD) systems using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) data may be developed to help localize prostate cancer and guide biopsy, avoiding random sampling of the whole gland. The purpose of this study is to present a DCE-MRI CAD system, which calculates the likelihood of malignancy in a given area of the prostate by combining model-based and model-free parameters. The dataset includes 10 patients with prostate cancer, with a total of 13 foci of adenocarcinoma. The post-processing is based on the following steps: testing of registration quality, noise filtering, and extracting the proposed features needed to the CAD. Parameters with the best performance in discriminating between normal and cancer regions are selected by computing the area under the ROC curve, and by evaluating the correlation between pairs of features. A 6-dimensional parameters vector is generated for each pixel and fed into a Bayesian classifier, in which the output is the probability of malignancy. The classification performance is estimated using the leave-one-out method. The resulting area under the ROC curve is 0.899 (95%CI:0.893-0.905); sensitivity and specificity are 82.4% and 82.1% respectively at the best cut-off point (0.352). Preliminary results show that the system is accurate in detecting areas of the gland that are involved by tumor. Further studies will be necessary to confirm these promising preliminary results.

  13. Masked assessment of MRI findings: is it possible to differentiate neuro-Behcet`s disease from other central nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Coban, O.; Bahar, S.; Akman-Demir, G.; Tasci, B.; Serdaroglu, P. [Univ. of Istanbul (Turkey). Dept. of Neurology; Yurdakul, S.; Yazici, H. [Univ. of Istanbul (Turkey). Dept. of Internal Medicine

    1999-04-01

    Two neuroradiologists reviewed MRI studies of 34 patients with neuro-Behcet`s disease (NBD), 22 with multiple sclerosis (MS) and 7 with systemic lupus erythematosus (SLE) with central nervous system involvement, masked to the clinical diagnosis, age and sex of the patients. Of the patients with NBD 12 were in an acute attack; the others had chronic disease. MRI was assessed using a set of criteria, looking at atrophy, the site of discrete parenchymal lesions, regions of predominant involvement and the extent of the lesion(s). The observers also made a guess at the clinical diagnosis. The brain stem and/or basal ganglia were the most predominantly involved sites in all patients with acute NBD; 75 % of these lesions were large and confluent, mainly extending from the brain stem to the diencephalon and basal ganglia. However, in chronic cases, the predominant involvement was in the brain stem and/or basal ganglia in only 36 %, and in cerebral hemisphere white matter in another 36 %; 27 % of these patients showed no parenchymal lesion. Hemisphere white-matter lesions were equally distributed between periventricular and other areas in NBD, while in MS more were periventricular, and in SLE more were nonperiventricular. Brain-stem atrophy was seen in 21 % of patients with NBD, with a specificity of 96.5 %. In the absence of cortical atrophy, its specificity was 100 %. The attempt at making a radiological diagnosis was successful in all cases of acute NBD and 95.5 % of patients with MS, but in only 40 % of patients with chronic NBD. Most of this latter groups MRI studies were interpreted as MS. An extensive lesion involving the brain stem and basal ganglia seemed to be diagnostic of acute NBD. However, hemisphere white-matter lesions could not be differentiated from those in MS. (orig.) With 3 figs., 6 tabs., 18 refs.

  14. An Intelligent System Proposal for Improving the Safety and Accessibility of Public Transit by Highway.

    Science.gov (United States)

    García, Carmelo R; Quesada-Arencibia, Alexis; Cristóbal, Teresa; Padrón, Gabino; Pérez, Ricardo; Alayón, Francisco

    2015-08-18

    The development of public transit systems that are accessible and safe for everyone, including people with special needs, is an objective that is justified from the civic and economic points of view. Unfortunately, public transit services are conceived for people who do not have reduced physical or cognitive abilities. In this paper, we present an intelligent public transit system by highway with the goal of facilitating access and improving the safety of public transit for persons with special needs. The system is deployed using components that are commonly available in transport infrastructure, e.g., sensors, mobile communications systems, and positioning systems. In addition, the system can operate in non-urban transport contexts, e.g., isolated rural areas, where the availability of basic infrastructure, such as electricity and communications infrastructures, is not always guaranteed. To construct the system, the principles and techniques of Ubiquitous Computing and Ambient Intelligence have been employed. To illustrate the utility of the system, two cases of services rendered by the system are described: the first case involves a surveillance system to guarantee accessibility at bus stops; the second case involves a route assistant for blind people.

  15. An Intelligent System Proposal for Improving the Safety and Accessibility of Public Transit by Highway

    Directory of Open Access Journals (Sweden)

    Carmelo R. García

    2015-08-01

    Full Text Available The development of public transit systems that are accessible and safe for everyone, including people with special needs, is an objective that is justified from the civic and economic points of view. Unfortunately, public transit services are conceived for people who do not have reduced physical or cognitive abilities. In this paper, we present an intelligent public transit system by highway with the goal of facilitating access and improving the safety of public transit for persons with special needs. The system is deployed using components that are commonly available in transport infrastructure, e.g., sensors, mobile communications systems, and positioning systems. In addition, the system can operate in non-urban transport contexts, e.g., isolated rural areas, where the availability of basic infrastructure, such as electricity and communications infrastructures, is not always guaranteed. To construct the system, the principles and techniques of Ubiquitous Computing and Ambient Intelligence have been employed. To illustrate the utility of the system, two cases of services rendered by the system are described: the first case involves a surveillance system to guarantee accessibility at bus stops; the second case involves a route assistant for blind people.

  16. Development of a Multidimensional Additive Points System for Determining Access to Rheumatology Services.

    Science.gov (United States)

    White, Douglas; Solanki, Kamal; Quincey, Vicki; Minett, Andrew; Tam, Gordon; Doube, Alan; Naden, Ray

    2015-08-01

    In many countries, including New Zealand, the demand for rheumatology services exceeds their supply, resulting in some patients experiencing long delays or being denied access. The principal aim of this work was to create a validated, transparent, and fair system for determining access to rheumatology services. A panel of 5 rheumatologists, 6 primary care physicians, and 4 nurse specialists ranked a series of 25 clinical scenarios in order of priority to see a rheumatologist. Important determining factors were weighted in an iterative process to generate a multidimensional additive point score to determine access to rheumatology service. The score comprises 6 domains of 2 to 4 items weighted to give a total score out of 100. The effect of the problem on the patient's life and role, the presence of an inflammatory rheumatic disease, appropriateness of current treatment, and the ability of the rheumatologist to influence the current symptoms and future prognosis were felt to be critical factors in determining access to the service. The score showed a strong correlation with the rankings agreed by the clinical panel, and the overall intraclass correlation coefficient for the rheumatologists was 0.698. Our score has face validity, is easy to perform, and has been assessed by an independent panel of rheumatologists as providing a fair system for determining access to rheumatology services. The system is acceptable to primary care physicians and has been adopted by our local primary care organizations.

  17. MRI of the Prostate

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Prostate Magnetic resonance imaging (MRI) of the prostate ... limitations of MRI of the Prostate? What is MRI of the Prostate? Magnetic resonance imaging (MRI) is ...

  18. Error correction coding for frequency-hopping multiple-access spread spectrum communication systems

    Science.gov (United States)

    Healy, T. J.

    1982-01-01

    A communication system which would effect channel coding for frequency-hopped multiple-access is described. It is shown that in theory coding can increase the spectrum utilization efficiency of a system with mutual interference to 100 percent. Various coding strategies are discussed and some initial comparisons are given. Some of the problems associated with implementing the type of system described here are discussed.

  19. Transparent image access in a distributed picture archiving and communications system: The master database broker

    OpenAIRE

    Cox, R D; Henri, C. J.; Rubin, R. K.

    1999-01-01

    A distributed design is the most cost-effective system for small- to medium-scale picture archiving and communications systems (PACS) implementations. However, the design presents an interesting challenge to developers and implementers: to make stored image data, distributed throughout the PACS network, appear to be centralized with a single access point for users. A key component for the distributed system is a central or master database, containing all the studies that have been scanned int...

  20. Quality Test Template toward Multi-user Access Control of Internet-Based System

    Directory of Open Access Journals (Sweden)

    Nan Nie

    2011-06-01

    Full Text Available Aiming at three kinds of Internet-based system quality problems, which is performance, liability and security, the paper proposes a kind of test template during multi-user login and resource access control, which includes test requirement, login script, role-resource correlating and mutation test technique. Some Internet-based systems are tested and diagnosed by automation test technique of test template. At last, system quality can be verified and improved through the realization mechanism of test template.

  1. Request Stream Control for the Access to Broadband Multimedia Educational Resources in the Distance Learning System

    Directory of Open Access Journals (Sweden)

    Irina Pavlovna Bolodurina

    2013-10-01

    Full Text Available This article presents a model of queuing system for broadband multimedia educational resources, as well as a model of access to a hybrid cloud system storage. These models are used to enhance the efficiency of computing resources in a distance learning system. An additional OpenStack control module has been developed to achieve the distribution of request streams and balance the load between cloud nodes.

  2. Using geographic information system tools to improve access to MS specialty care in Veterans Health Administration.

    Science.gov (United States)

    Culpepper, William J; Cowper-Ripley, Diane; Litt, Eric R; McDowell, Tzu-Yun; Hoffman, Paul M

    2010-01-01

    Access to appropriate and timely healthcare is critical to the overall health and well-being of patients with chronic diseases. In this study, we used geographic information system (GIS) tools to map Veterans Health Administration (VHA) patients with multiple sclerosis (MS) and their access to MS specialty care. We created six travel-time bands around VHA facilities with MS specialty care and calculated the number of VHA patients with MS who resided in each time band and the number of patients who lived more than 2 hours from the nearest specialty clinic in fiscal year 2007. We demonstrate the utility of using GIS tools in decision-making by providing three examples of how patients' access to care is affected when additional specialty clinics are added. The mapping technique used in this study provides a powerful and valuable tool for policy and planning personnel who are evaluating how to address underserved populations and areas within the VHA healthcare system.

  3. Seed quality of common bean accessions under organic and conventional farming systems

    Directory of Open Access Journals (Sweden)

    Diego Medeiros Gindri

    2017-06-01

    Full Text Available Agrobiodiversity is essential for a sustainable food production, and the knowledge of the potential characteristics of landrace seeds may prompt farmers to adopt the habit of seed conservation for this species. This study aimed at categorizing landrace and commercial common bean (Phaseolus vulgaris L. accessions, according to the physiological quality (viability and vigor of seeds produced in the field, during two growing seasons, under organic and conventional farming systems. Germination percentage, field emergence, electrical conductivity, accelerated aging, cold test and seedling length were assessed. The landrace bean accessions exhibit diversity in the physiological seed quality, in terms of their viability and vigor. No differences were observed between the farming systems, in relation to the physiological quality of the seeds produced. The categorization of landrace common bean accessions allows to identify those with superior physiological seed quality.

  4. Combined PET/MRI

    DEFF Research Database (Denmark)

    Bailey, D. L.; Pichler, B. J.; Gückel, B.

    2015-01-01

    This paper summarises key themes and discussions from the 4th international workshop dedicated to the advancement of the technical, scientific and clinical applications of combined positron emission tomography (PET)/magnetic resonance imaging (MRI) systems that was held in Tübingen, Germany, from...... February 23 to 27, 2015. Specifically, we summarise the three days of invited presentations from active researchers in this and associated fields augmented by round table discussions and dialogue boards with specific topics. These include the use of PET/MRI in cardiovascular disease, paediatrics, oncology......, neurology and multi-parametric imaging, the latter of which was suggested as a key promoting factor for the wider adoption of integrated PET/MRI. Discussions throughout the workshop and a poll taken on the final day demonstrated that attendees felt more strongly that PET/MRI has further advanced in both...

  5. Chondrogenic Lesions of the Skeletal System Using Radiographs, CT and MRI

    Directory of Open Access Journals (Sweden)

    Akbar Bonakdarpour

    2011-05-01

    Full Text Available Benign Tumors: Chondroma, chondroblastoma,"nchondromyxoid fibroma, osteochondroma"nChondroma"n1. Enchondroma"n2. Periosteal Chondroma"n3. Enchondromatosis"n4. Metachondromatosis"nEnchondroma is a benign metaphyseal tumor. The"nmajor differential diagnoses are bone infarct and"nchondrosarcoma. Calcification in enchondroma"nhas a popcorn appearance and on radiographs and"nCT they may be counted. Calcified bone infarct"nhas an appearance similar to rotten metal. Central"nchondrosarcoma shows cortical erosion more than"ntwo thirds of the thickness of cortex and also periosteal"nreaction. Pain and growth of lesion in adulthood raises"nthe possibility of malignant transformation."nPeriosteal chondroma: This lesion arises from the"nperiosteum without involving the medullary bone."nThe most common location is the upper humerus."nEnchondromatosis reveals multiple enchondromas,"npredominantly involving one side of the skeleton."nMalignant transformation is the major complication"nof enchondromatosis. In malignant transformation,"nMRI shows that perichondrium is more than 1 cm"nthick in adults and more than 3 cm thick in children."nIn the hands and feet, enchondromatosis should not"nbe confused with fibrous dysplasia. Mafucci syndrome"nis enchondromatosis associated with cavernous"nhemangiomas with a prognosis worse than enchondr"nomatosis."nMultiple hereditary cartilaginous exostoses: This is"nof metaphyseal origin and pedunculated forms grow"naway from the adjacent joint. Sessile osteochondromas"nare broad based; if their surface is irregular they are"nsuspicious of malignancy. Pain and growth of the"nlesion after closure of the epiphyseal plate are warning"nsigns of malignant transformation. In malignant"ntransformation MRI shows that perichondrium is"nmore than 1 cm thick in adults and more than 3 cm"nthick in children."nChondroblastoma: This is a benign tumor, seen before"nclosure of epiphyseal plate, with a sclerotic border."n30 to 50% show

  6. SU-E-J-210: Characterizing Tissue Equivalent Materials for the Development of a Dual MRI-CT Heterogeneous Anthropomorphic Phantom Designed Specifically for MRI Guided Radiotherapy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Steinmann, A; Stafford, R; Yung, J; Followill, D [UT MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: MRI guided radiotherapy (MRIgRT) is an emerging technology which will eventually require a proficient quality auditing system. Due to different principles in which MR and CT acquire images, there is a need for a multi-imaging-modality, end-to-end QA phantom for MRIgRT. The purpose of this study is to identify lung, soft tissue, and tumor equivalent substitutes that share similar human-like CT and MR properties (i.e. Hounsfield units and relaxation times). Methods: Materials of interested such as common CT QA phantom materials, and other proprietary gels/silicones from Polytek, SmoothOn, and CompositeOne were first scanned on a GE 1.5T Signa HDxT MR. Materials that could be seen on both T1-weighted and T2-weighted images were then scanned on a GE Lightspeed RT16 CT simulator and a GE Discovery 750HD CT scanner and their HU values were then measured. The materials with matching HU values of lung (−500 to −700HU), muscle (+40HU) and soft tissue (+100 to +300HU) were further scanned on GE 1.5T Signa HDx to measure their T1 and T2 relaxation times from varying parameters of TI and TE. Results: Materials that could be visualized on T1-weighted and T2-weighted images from a 1.5T MR unit and had an appropriate average CT number, −650, −685, 46,169, and 168 HUs were: compressed cork saturated with water, Polytek Platsil™ Gel-00 combined with mini styrofoam balls, radiotherapy bolus material, SmoothOn Dragon-Skin™ and SmoothOn Ecoflex™, respectively. Conclusion: Post processing analysis is currently being performed to accurately map T1 and T2 values for each material tested. From previous MR visualization and CT examinations it is expected that Dragon-Skin™, Ecoflex™ and bolus will have values consistent with tissue and tumor substitutes. We also expect compressed cork statured with water, and Polytek™-styrofoam combination to have approximate T1 and T2 values suitable for lung-equivalent materials.

  7. A fully automated system for quantification of background parenchymal enhancement in breast DCE-MRI

    Science.gov (United States)

    Ufuk Dalmiş, Mehmet; Gubern-Mérida, Albert; Borelli, Cristina; Vreemann, Suzan; Mann, Ritse M.; Karssemeijer, Nico

    2016-03-01

    Background parenchymal enhancement (BPE) observed in breast dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) has been identified as an important biomarker associated with risk for developing breast cancer. In this study, we present a fully automated framework for quantification of BPE. We initially segmented fibroglandular tissue (FGT) of the breasts using an improved version of an existing method. Subsequently, we computed BPEabs (volume of the enhancing tissue), BPErf (BPEabs divided by FGT volume) and BPErb (BPEabs divided by breast volume), using different relative enhancement threshold values between 1% and 100%. To evaluate and compare the previous and improved FGT segmentation methods, we used 20 breast DCE-MRI scans and we computed Dice similarity coefficient (DSC) values with respect to manual segmentations. For evaluation of the BPE quantification, we used a dataset of 95 breast DCE-MRI scans. Two radiologists, in individual reading sessions, visually analyzed the dataset and categorized each breast into minimal, mild, moderate and marked BPE. To measure the correlation between automated BPE values to the radiologists' assessments, we converted these values into ordinal categories and we used Spearman's rho as a measure of correlation. According to our results, the new segmentation method obtained an average DSC of 0.81 0.09, which was significantly higher (p<0.001) compared to the previous method (0.76 0.10). The highest correlation values between automated BPE categories and radiologists' assessments were obtained with the BPErf measurement (r=0.55, r=0.49, p<0.001 for both), while the correlation between the scores given by the two radiologists was 0.82 (p<0.001). The presented framework can be used to systematically investigate the correlation between BPE and risk in large screening cohorts.

  8. 49 CFR 37.185 - Fleet accessibility requirement for OTRB fixed-route systems of large operators.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Fleet accessibility requirement for OTRB fixed....185 Fleet accessibility requirement for OTRB fixed-route systems of large operators. Each large... percent of the buses in its fleet with which it provides fixed-route service are readily accessible to...

  9. Digital Model of Human Lower Extremity Musculoskeletal System Based on CT & MRI

    Institute of Scientific and Technical Information of China (English)

    尚鹏; 王成焘; 王立

    2004-01-01

    A new method to reconstruct a comparatively complete muscle model of the human lower limb from CT and MRI data is presented. Topological structure of more than fourteen muscles is built and coordinates of origin and insertion points are given.Based on this model, straight-line model and centroid-line muscle model are acquired. Muscle force prediction is discussed according to the model reconstructed, and a multi-objective optimization method is put forward for evaluating muscle forces of the human lower extremity.

  10. Clinical routine implantation of a dual chamber pacemaker system designed for safe use with MRI: a single center, retrospective study on lead performance of Medtronic lead 5086MRI in comparison to Medtronic leads 4592-53 and 4092-58.

    Science.gov (United States)

    Wollmann, C G; Thudt, K; Vock, P; Globits, S; Mayr, H

    2011-12-01

    We report our experience concerning lead performance and re-surgery rate of the Medtronic EnRhythm MRI SureScan pacemaker system (MRI-PM) in comparison to standard pacemaker (PM) systems and leads used at our institution. All patients (except patients with transvenous left ventricular leads) with successful PM implantation performed at our institution from 1 March 2009 to 31 October 2009 were included in this analysis and followed until mid January 2010. Lead measurements (assessed at implantation, prehospital discharge interrogation (1st follow-up) and at the first scheduled out-patient follow-up (2nd follow-up) were compared between atrial leads 4592-53 cm and 5086MRI-52 cm (lead group 1), and between ventricular leads 4092-58 cm and 5086MRI-52 cm/-58 cm (lead group 2), respectively. Causes for re-operations were assessed and compared between patients with standard dual chamber PM (DC-PM) and the MRI-PM. A total of 140 patients (VVI-PM: 36 patients; DDD-PM: 102 patients; biventricular PM: 1 patient) were successfully implanted with a PM within the implantation period. Two patients with transvenous left ventricular leads were excluded from further analysis. In an atrial position, lead 4592 was implanted in 51 patients and lead 5086MRI-52 cm was implanted in 40 patients, respectively. Ventricular leads were lead 4092-58 cm (64 patients) and lead 5086MRI (41 patients), respectively. Patients were followed for 26 ± 11 weeks. Comparison of lead measurements of lead group 1 showed significant differences for pacing impedance and pacing threshold at implantation, and for sensing at the 2nd follow-up. Comparison of lead measurements within lead group 2 showed significant differences for pacing impedance at implantation, for pacing threshold at the 1st follow-up, and for sensing, pacing threshold, and impedance at the 2nd follow-up. All assessed mean values were favorable for all leads at any follow-up. The number of re-operations was high in

  11. MRI-Compatible Pneumatic Robot for Transperineal Prostate Needle Placement.

    Science.gov (United States)

    Fischer, Gregory S; Iordachita, Iulian; Csoma, Csaba; Tokuda, Junichi; Dimaio, Simon P; Tempany, Clare M; Hata, Nobuhiko; Fichtinger, Gabor

    2008-06-01

    Magnetic resonance imaging (MRI) can provide high-quality 3-D visualization of prostate and surrounding tissue, thus granting potential to be a superior medical imaging modality for guiding and monitoring prostatic interventions. However, the benefits cannot be readily harnessed for interventional procedures due to difficulties that surround the use of high-field (1.5T or greater) MRI. The inability to use conventional mechatronics and the confined physical space makes it extremely challenging to access the patient. We have designed a robotic assistant system that overcomes these difficulties and promises safe and reliable intraprostatic needle placement inside closed high-field MRI scanners. MRI compatibility of the robot has been evaluated under 3T MRI using standard prostate imaging sequences and average SNR loss is limited to 5%. Needle alignment accuracy of the robot under servo pneumatic control is better than 0.94 mm rms per axis. The complete system workflow has been evaluated in phantom studies with accurate visualization and targeting of five out of five 1 cm targets. The paper explains the robot mechanism and controller design, the system integration, and presents results of preliminary evaluation of the system.

  12. High security chaotic multiple access scheme for visible light communication systems with advanced encryption standard interleaving

    Science.gov (United States)

    Qiu, Junchao; Zhang, Lin; Li, Diyang; Liu, Xingcheng

    2016-06-01

    Chaotic sequences can be applied to realize multiple user access and improve the system security for a visible light communication (VLC) system. However, since the map patterns of chaotic sequences are usually well known, eavesdroppers can possibly derive the key parameters of chaotic sequences and subsequently retrieve the information. We design an advanced encryption standard (AES) interleaving aided multiple user access scheme to enhance the security of a chaotic code division multiple access-based visible light communication (C-CDMA-VLC) system. We propose to spread the information with chaotic sequences, and then the spread information is interleaved by an AES algorithm and transmitted over VLC channels. Since the computation complexity of performing inverse operations to deinterleave the information is high, the eavesdroppers in a high speed VLC system cannot retrieve the information in real time; thus, the system security will be enhanced. Moreover, we build a mathematical model for the AES-aided VLC system and derive the theoretical information leakage to analyze the system security. The simulations are performed over VLC channels, and the results demonstrate the effectiveness and high security of our presented AES interleaving aided chaotic CDMA-VLC system.

  13. Optimizing a machine learning based glioma grading system using multi-parametric MRI histogram and texture features.

    Science.gov (United States)

    Zhang, Xin; Yan, Lin-Feng; Hu, Yu-Chuan; Li, Gang; Yang, Yang; Han, Yu; Sun, Ying-Zhi; Liu, Zhi-Cheng; Tian, Qiang; Han, Zi-Yang; Liu, Le-De; Hu, Bin-Quan; Qiu, Zi-Yu; Wang, Wen; Cui, Guang-Bin

    2017-07-18

    Current machine learning techniques provide the opportunity to develop noninvasive and automated glioma grading tools, by utilizing quantitative parameters derived from multi-modal magnetic resonance imaging (MRI) data. However, the efficacies of different machine learning methods in glioma grading have not been investigated.A comprehensive comparison of varied machine learning methods in differentiating low-grade gliomas (LGGs) and high-grade gliomas (HGGs) as well as WHO grade II, III and IV gliomas based on multi-parametric MRI images was proposed in the current study. The parametric histogram and image texture attributes of 120 glioma patients were extracted from the perfusion, diffusion and permeability parametric maps of preoperative MRI. Then, 25 commonly used machine learning classifiers combined with 8 independent attribute selection methods were applied and evaluated using leave-one-out cross validation (LOOCV) strategy. Besides, the influences of parameter selection on the classifying performances were investigated. We found that support vector machine (SVM) exhibited superior performance to other classifiers. By combining all tumor attributes with synthetic minority over-sampling technique (SMOTE), the highest classifying accuracy of 0.945 or 0.961 for LGG and HGG or grade II, III and IV gliomas was achieved. Application of Recursive Feature Elimination (RFE) attribute selection strategy further improved the classifying accuracies. Besides, the performances of LibSVM, SMO, IBk classifiers were influenced by some key parameters such as kernel type, c, gama, K, etc. SVM is a promising tool in developing automated preoperative glioma grading system, especially when being combined with RFE strategy. Model parameters should be considered in glioma grading model optimization.

  14. Japan Meteorological Agency/Meteorological Research Institute-Coupled Prediction System version 1 (JMA/MRI-CPS1) for operational seasonal forecasting

    Science.gov (United States)

    Takaya, Yuhei; Yasuda, Tamaki; Fujii, Yosuke; Matsumoto, Satoshi; Soga, Taizo; Mori, Hirotoshi; Hirai, Masayuki; Ishikawa, Ichiro; Sato, Hitoshi; Shimpo, Akihiko; Kamachi, Masafumi; Ose, Tomoaki

    2017-01-01

    This paper describes the operational seasonal prediction system of the Japan Meteorological Agency (JMA), the Japan Meteorological Agency/Meteorological Research Institute-Coupled Prediction System version 1 (JMA/MRI-CPS1), which was in operation at JMA during the period between February 2010 and May 2015. The predictive skill of the system was assessed with a set of retrospective seasonal predictions (reforecasts) covering 30 years (1981-2010). JMA/MRI-CPS1 showed reasonable predictive skill for the El Niño-Southern Oscillation, comparable to the skills of other state-of-the-art systems. The one-tiered approach adopted in JMA/MRI-CPS1 improved its overall predictive skills for atmospheric predictions over those of the two-tiered approach of the previous uncoupled system. For 3-month predictions with a 1-month lead, JMA/MRI-CPS1 showed statistically significant skills in predicting 500-hPa geopotential height and 2-m temperature in East Asia in most seasons; thus, it is capable of providing skillful seasonal predictions for that region. Furthermore, JMA/MRI-CPS1 was superior overall to the previous system for atmospheric predictions with longer (4-month) lead times. In particular, JMA/MRI-CPS1 was much better able to predict the Asian Summer Monsoon than the previous two-tiered system. This enhanced performance was attributed to the system's ability to represent atmosphere-ocean coupled variability over the Indian Ocean and the western North Pacific from boreal winter to summer following winter El Niño events, which in turn influences the East Asian summer climate through the Pacific-Japan teleconnection pattern. These substantial improvements obtained by using an atmosphere-ocean coupled general circulation model underpin its success in providing more skillful seasonal forecasts on an operational basis.

  15. Effects of Job Accessibility Improved by Public Transport System: Natural Experimental Evidence from the Copenhagen Metro

    DEFF Research Database (Denmark)

    Pons Rotger, Gabriel Angel; Nielsen, Thomas Alexander Sick

    2015-01-01

    and Metro system resulting from the construction of a new terminal Metro station connecting southern townships to Copenhagen city centre. The results show that public transport based job accessibility has a positive and permanent effect on individual earnings. The increase in earnings is associated...

  16. Effects of Job Accessibility Improved by Public Transport System: Natural Experimental Evidence from the Copenhagen Metro

    DEFF Research Database (Denmark)

    Rotger, Gabriel Pons; Sick Nielsen, Thomas

    2015-01-01

    and Metro system due to the construction of a new terminal Metro station connecting southern townships to the city centre of Copenhagen. The results show that public transport based job accessibility has a positive and permanent effect on individual earnings. The increase in earnings is associated...

  17. Hacking Blackboard: Customizing Access to Library Resources through the Blackboard Course Management System

    Science.gov (United States)

    Kellam, Lynda M.; Cox, Richard; Winkler, Hannah

    2009-01-01

    Academic libraries have long been trying to gain access to users through their favorite online spaces, such as social networking sites. In this article a project of the University of North Carolina at Greensboro's University Libraries, which integrated library resources with the campus course management system, Blackboard, is detailed. The main…

  18. 28 CFR 16.92 - Exemption of Environment and Natural Resources Division Systems-limited access.

    Science.gov (United States)

    2010-07-01

    ....92 Exemption of Environment and Natural Resources Division Systems—limited access. (a)(1) The...) Environment and Natural Resources Division Case and Related Files System, JUSTICE/ENRD-003. (ii) (2) These..., the applicable exemption may be waived by the Environment and Natural Resources Division. (b)...

  19. An API-based search system for one click access to information

    NARCIS (Netherlands)

    Ionita, Dan; Tax, Niek; Hiemstra, Djoerd

    2013-01-01

    This paper proposes a prototype One Click access system, based on previous work in the field and the related 1CLICK-2@NTCIR10 task. The proposed solution integrates methods from into a three tier algorithm: query categorization, information extraction and output generation and offers suggestions on

  20. Hacking Blackboard: Customizing Access to Library Resources through the Blackboard Course Management System

    Science.gov (United States)

    Kellam, Lynda M.; Cox, Richard; Winkler, Hannah

    2009-01-01

    Academic libraries have long been trying to gain access to users through their favorite online spaces, such as social networking sites. In this article a project of the University of North Carolina at Greensboro's University Libraries, which integrated library resources with the campus course management system, Blackboard, is detailed. The main…

  1. The integration of open access journals in the scholarly communication system: Three science fields

    DEFF Research Database (Denmark)

    Faber Frandsen, Tove

    2009-01-01

    The greatest number of open access journals (OAJs) is found in the sciences and their influence is growing. However, there are only a few studies on the acceptance and thereby integration of these OAJs in the scholarly communication system. Even fewer studies provide insight into the differences...

  2. Accessibility Evaluation of Online Learning Management System for Persons with Visual Impairment

    Science.gov (United States)

    Suwannawut, Nantanoot

    2014-01-01

    Many academic institutions around the world are utilizing and investing in online learning management systems (LMS). While several research studies have examined the functionality of this type of technology, little attention has been paid to accessibility issues, in particular to the complex web-based interfaces for learners with disabilities,…

  3. Massive M2M Access with Reliability Guarantees in LTE Systems

    DEFF Research Database (Denmark)

    Madueño, Germán Corrales; Kiilerich Pratas, Nuno; Stefanovic, Cedomir

    2015-01-01

    Machine-to-Machine (M2M) communications are one of the major drivers of the cellular network evolution towards 5G systems. One of the key challenges is on how to provide reliability guarantees to each accessing device in a situation in which there is a massive number of almost-simultaneous arrivals...

  4. 28 CFR 16.80 - Exemption of Office of Professional Responsibility System-limited access.

    Science.gov (United States)

    2010-07-01

    ....80 Exemption of Office of Professional Responsibility System—limited access. (a) The following system...), (e)(5) and (8), (f) and (g): (1) Office of Professional Responsibility Record Index (JUSTICE/OPR-001... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Exemption of Office of Professional...

  5. Design and Implementation of File Access and Control System Based on Dynamic Web

    Institute of Scientific and Technical Information of China (English)

    GAO Fuxiang; YAO Lan; BAO Shengfei; YU Ge

    2006-01-01

    A dynamic Web application, which can help the departments of enterprise to collaborate with each other conveniently, is proposed. Several popular design solutions are introduced at first. Then, dynamic Web system is chosen for developing the file access and control system. Finally, the paper gives the detailed process of the design and implementation of the system, which includes some key problems such as solutions of document management and system security. Additionally, the limitations of the system as well as the suggestions of further improvement are also explained.

  6. Email based remote access and surveillance system for smart home infrastructure

    Directory of Open Access Journals (Sweden)

    Pooshkar Rajiv

    2016-09-01

    Full Text Available With the rapid rise of Internet of Things in public domain, people expect fast, reliable and on-demand home security via the Internet. However, existing remote home surveillance systems place a very rigid constraint on authentication and require customized hardware and software. In this paper we have proposed an ingenious and reliable internet based, home access system for smart homes that can be easily deployed on generic hardware. The proposed architecture uses popular email service providers to notify and update the user about the home access. It sends an email to the owner with the attached picture of the person who is at the door. It also incorporates a protected mechanism to give access of the door to a remote user by responding to that email. It essentially means that we can view and give access to the person at our door via sending and receiving an email. Furthermore, an image processing based mechanism has also been incorporated to provide access without email, to few selected personnel who are trusted by the owner. It works by capturing and comparing the visitor's image with the stored images in the database. Perceptual hashing or fingerprint matching algorithm is used for comparison purposes. Similarity percentage based on hamming distance was evaluated, and the similarity threshold for providing access was set. The simulations were performed in rigorous environment. The efficiency of the hashing algorithm was found to be 97% at the similarity threshold of 95%. The results validate that the average latency is only 155 ms with low standard deviation. The CPU utilization remained quite low with a minimum value of 10 MHz and a maximum value of 30 MHz when the payload size of the sent mail was increased to 1500 kB. Thus, the proposed system can be used for developing a larger low power infrastructure.

  7. Health and healthcare access among Zambia's female prisoners: a health systems analysis.

    Science.gov (United States)

    Topp, Stephanie M; Moonga, Clement N; Mudenda, Constance; Luo, Nkandu; Kaingu, Michael; Chileshe, Chisela; Magwende, George; Heymann, Jody S; Henostroza, German

    2016-09-26

    Research exploring the drivers of health outcomes of women who are in prison in low- and middle-income settings is largely absent. This study aimed to identify and examine the interaction between structural, organisational and relational factors influencing Zambian women prisoners' health and healthcare access. We conducted in-depth interviews of 23 female prisoners across four prisons, as well as 21 prison officers and health care workers. The prisoners were selected in a multi-stage sampling design with a purposive selection of prisons followed by a random sampling of cells and of female inmates within cells. Largely inductive thematic analysis was guided by the concepts of dynamic interaction and emergent behaviour, drawn from the theory of complex adaptive systems. We identified compounding and generally negative effects on health and access to healthcare from three factors: i) systemic health resource shortfalls, ii) an implicit prioritization of male prisoners' health needs, and iii) chronic and unchecked patterns of both officer- and inmate-led victimisation. Specifically, women's access to health services was shaped by the interactions between lack of in-house clinics, privileged male prisoner access to limited transport options, and weak responsiveness by female officers to prisoner requests for healthcare. Further intensifying these interactions were prisoners' differential wealth and access to family support, and appointments of senior 'special stage' prisoners which enabled chronic victimisation of less wealthy or less powerful individuals. This systems-oriented analysis revealed how Zambian women's prisoners' health and access to healthcare is influenced by weak resourcing for prisoner health, administrative biases, and a prevailing organisational and inmate culture. Findings highlight the urgent need for investment in structural improvements in health service availability but also interventions to reform the organisational culture which shapes

  8. Pediatric MRI

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIH Study of Normal Brain Development is a longitudinal study using anatomical MRI, diffusion tensor imaging (DTI), and MR spectroscopy (MRS) to map pediatric...

  9. Knee MRI

    Science.gov (United States)

    ... air-conditioned and well-lit. Some scanners have music to help you pass the time. When the ... that magnetic resonance imaging harms the fetus, pregnant women usually are advised not to have an MRI ...

  10. Combinatory Spread—Spectrum Multiple—Access Based on Residue Number System:System and Performance

    Institute of Scientific and Technical Information of China (English)

    YangLieliang; LiChengshu

    1995-01-01

    A combinatory direct-sequence based on residue number system(RNS),spread spec-trum multiple-access communication system model is presented.Under this communication envi-ronment,each user is assigned a set of∑i=1lmi(when i≠j,gcd(mi,mj)=1)othogonal sequences;Each receiver has ∑i=1l micorrelators used for despread,log2(пi=1lmi) information bits can be trans-mitted in a symbol period.We obtain approximations for the multiuser probability of error when the channel noise is a combination of additive white Gaussian noise (AWGN)and multiple-access interference .In section4,we compare the performance such as transmission capability,system structure,and the probability of error with the system proposed by P.K.Enge.

  11. RFID-Based Monitoring And Access Control System For Parliamentary Campus

    Directory of Open Access Journals (Sweden)

    Sai Thu Rein Htun

    2015-08-01

    Full Text Available This paper is to implement monitoring and access control system based on RFID and Zigbee technology which can be used at Parliamentary Campus. Nowadays RFID technology is widely used for access control system because it is cheap waterproof and easy to use as well as it contains unique EPC electronic protect code .In addition Zigbee wireless module is cost-effective and can be reliable for security. Sothis system consists of RFID tag RFID reader Arduino Uno and Zigbee. This system can also be used for industrial amp commercial and security HVAC closures. This paper describes the results of point-to-point connection and point-to-multipoint connection using Zigbee and RFID technology.

  12. Closed Catheter Access System Implementation in Reducing Bloodstream Infection Rate in Low Birth Weight Preterm Infants

    Directory of Open Access Journals (Sweden)

    Lily eRundjan

    2015-03-01

    Full Text Available Background Bloodstream infection (BSI is one of the significant causes of morbidity and mortality encountered in a neonatal intensive care unit (NICU, especially in developing countries. Despite the implementation of infection control practices, such as strict hand hygiene, the BSI rate in our hospital is still high. The use of a closed catheter access system to reduce BSI related to intravascular catheter has hitherto never been evaluated in our hospital. Objective To determine the effects of closed catheter access system implementation in reducing the BSI rate in preterm neonates with low birth weight.Methods Randomized clinical trial was conducted on 60 low birth weight preterm infants hospitalized in the neonatal unit at Cipto Mangunkusumo Hospital, Jakarta, Indonesia from June to September, 2013. Randomized subjects either received a closed or non-closed catheter access system. Subjects were monitored for 2 weeks for the development of BSI based on clinical signs, abnormal infection parameters, and blood culture. Results Closed catheter access system implementation gave a protective effect towards the occurrence of culture-proven BSI (relative risk 0.095, 95% CI 0.011 to 0.85, p=0.026. Risk of culture-proven BSI in the control group was 10.545 (95% CI 1.227 to 90.662, p=0.026. BSI occurred in 75% of neonates without risk factors of infection in the control group compared to none in the study group.Conclusions The use of a closed catheter access system reduced the BSI in low birth weight preterm infants. Choosing the right device design, proper disinfection of device and appropriate frequency of connector change should be done simultaneously.

  13. Research and teaching access to a large clinical picture archiving and communication system

    OpenAIRE

    Harrison, Marc; Koh, Justin; Tran, Steven; Mongkolwat, Patanasak; Channin, David S.

    2001-01-01

    Purpose: To identify practical issues surrounding delivering digital images from picture archiving and communication systems (PACS) for research and teaching purposes. The complexity of Digital Imaging and Communications in Medicine (DICOM) access methods, security, patient confidentiality, PACS database integrity, portability, and scalability are discussed. A software prototype designed to resolve these issues is described.System Architecture: A six-component, three-tier, client server softw...

  14. A Novel Memory Structure for Embedded Systems: Flexible Sequential and Random Access Memory

    Institute of Scientific and Technical Information of China (English)

    Ying Chen; Karthik Ranganathan; Vasudev V. Pai; David J. Lilja; Kia Bazargan

    2005-01-01

    The on-chip memory performance of embedded systems directly affects the system designers' decision about how to allocate expensive silicon area. A novel memory architecture, flexible sequential and random access memory (FSRAM),is investigated for embedded systems. To realize sequential accesses, small "links" are added to each row in the RAM array to point to the next row to be prefetched. The potential cache pollution is ameliorated by a small sequential access buffer (SAB). To evaluate the architecture-level performance of FSRAM, we ran the Mediabench benchmark programs on a modified version of the SimpleScalar simulator. Our results show that the FSRAM improves the performance of a baseline processor with a 16KB data cache up to 55%, with an average of 9%; furthermore, the FSRAM reduces 53.1% of the data cache miss count on average due to its prefetching effect. We also designed RTL and SPICE models of the FSRAM, which show that the FSRAM significantly improves memory access time, while reducing power consumption, with negligible area overhead.

  15. Building a foundation for systems change: increasing access to physical activity programs for older adults.

    Science.gov (United States)

    Lachenmayr, Sue; Mackenzie, Geraldine

    2004-10-01

    Although 25% of U.S. adults are physically inactive, this percentage increases dramatically for older adults. Organizational change theory guided a state health department in identifying system gaps and developing strategies to expand programming for seniors. A survey of provider agencies in New Jersey assessed (a) capacity for physical activity programs for older adults, (b) accessibility of programs, and (c) barriers to providing programs. One hundred sixty agencies provided physical activity programs to almost 184,000 individuals annually. Fewer than one half of the agencies provided exercise programs for people with disabilities, and only 44% provided in-home programs. Eighty-two percent of program providers wanted to expand programming but cited lack of trained instructors and peer leaders, inadequate facility space, insufficient funding, and limited transportation resources as barriers. Sustaining older adult behavior change requires infrastructure that will ensure access to diverse physical activities. This article provides strategies to expand access to physical activity programs for older adults.

  16. MRI pattern of arthritis in systemic lupus erythematosus: a comparative study with rheumatoid arthritis and healthy subjects

    Energy Technology Data Exchange (ETDEWEB)

    Tani, Chiara; Possemato, Niccolo; Delle Sedie, Andrea; Bombardieri, Stefano; Mosca, Marta [University of Pisa, Rheumatology Unit, Department of Clinical and Experimental Medicine, Pisa (Italy); D' aniello, Dario; Caramella, Davide [Radiology Unit, University of Pisa, Pisa (Italy)

    2014-10-24

    In this study we aimed to describe the magnetic resonance imaging (MRI) pattern of the distribution of bone marrow edema (BME) and joint erosion in hands and wrists of patients with systemic lupus erythematosus (SLE) with arthritis in comparison with rheumatoid arthritis (RA) and healthy subjects (H). SLE patients with arthritis (n = 50), patients with RA (n = 22), and H (n = 48) were enrolled. Every patient underwent a non-dominant hand (2nd-5th metacarpophalangeal joints) and wrist MRI without contrast injection with a low-field extremity dedicated 0.2-Tesla instrument. BME was observed in two SLE patients in the hand (4 %) and in 15 in the wrist (13 %) versus three (30 %), and 14 (63 %) RA patients. No BME was found in H. Erosions were observed in the hand in 24 SLE patients (48 %), 15 RA patients (68 %), and 9 H (18 %); in the wrist, in 41 (82 %) SLE, all RA and 47 (97 %) H. The cumulative erosive burden in SLE was significantly higher than in H (c = 0.002) but similar to RA patients. Joint involvement of the wrist in SLE is similar to RA and is not as rare as expected, as shown by the comparison with healthy subjects. On the contrary, the involvement of the hand in SLE is significantly lower compared to RA. (orig.)

  17. A novel computer-aided diagnosis system for breast MRI based on feature selection and ensemble learning.

    Science.gov (United States)

    Lu, Wei; Li, Zhe; Chu, Jinghui

    2017-03-06

    Breast cancer is a common cancer among women. With the development of modern medical science and information technology, medical imaging techniques have an increasingly important role in the early detection and diagnosis of breast cancer. In this paper, we propose an automated computer-aided diagnosis (CADx) framework for magnetic resonance imaging (MRI). The scheme consists of an ensemble of several machine learning-based techniques, including ensemble under-sampling (EUS) for imbalanced data processing, the Relief algorithm for feature selection, the subspace method for providing data diversity, and Adaboost for improving the performance of base classifiers. We extracted morphological, various texture, and Gabor features. To clarify the feature subsets' physical meaning, subspaces are built by combining morphological features with each kind of texture or Gabor feature. We tested our proposal using a manually segmented Region of Interest (ROI) data set, which contains 438 images of malignant tumors and 1898 images of normal tissues or benign tumors. Our proposal achieves an area under the ROC curve (AUC) value of 0.9617, which outperforms most other state-of-the-art breast MRI CADx systems. Compared with other methods, our proposal significantly reduces the false-positive classification rate.

  18. Preclinical evaluation of a low-frequency transcranial MRI-guided focused ultrasound system in a primate model

    Science.gov (United States)

    McDannold, Nathan; Livingstone, Margaret; Barış Top, Can; Sutton, Jonathan; Todd, Nick; Vykhodtseva, Natalia

    2016-11-01

    This study investigated thermal ablation and skull-induced heating with a 230 kHz transcranial MRI-guided focused ultrasound (TcMRgFUS) system in nonhuman primates. We evaluated real-time acoustic feedback and aimed to understand whether cavitation contributed to the heating and the lesion formation. In four macaques, we sonicated thalamic targets at acoustic powers of 34-560 W (896-7590 J). Tissue effects evaluated with MRI and histology were compared to MRI-based temperature and thermal dose measurements, acoustic emissions recorded during the experiments, and acoustic and thermal simulations. Peak temperatures ranged from 46 to 57 °C, and lesions were produced in 5/8 sonicated targets. A linear relationship was observed between the applied acoustic energy and both the focal and brain surface heating. Thermal dose thresholds were 15-50 cumulative equivalent minutes at 43 °C, similar to prior studies at higher frequencies. Histology was also consistent with earlier studies of thermal effects in the brain. The system successfully controlled the power level and maintained a low level of cavitation activity. Increased acoustic emissions observed in 3/4 animals occurred when the focal temperature rise exceeded approximately 16 °C. Thresholds for thermally-significant subharmonic and wideband emissions were 129 and 140 W, respectively, corresponding to estimated pressure amplitudes of 2.1 and 2.2 MPa. Simulated focal heating was consistent with the measurements for sonications without thermally-significant acoustic emissions; otherwise it was consistently lower than the measurements. Overall, these results suggest that the lesions were produced by thermal mechanisms. The detected acoustic emissions, however, and their association with heating suggest that cavitation might have contributed to the focal heating. Compared to earlier work with a 670 kHz TcMRgFUS system, the brain surface heating was substantially reduced and the focal heating was higher with this

  19. Method for Evaluation of Outage Probability on Random Access Channel in Mobile Communication Systems

    Science.gov (United States)

    Kollár, Martin

    2012-05-01

    In order to access the cell in all mobile communication technologies a so called random-access procedure is used. For example in GSM this is represented by sending the CHANNEL REQUEST message from Mobile Station (MS) to Base Transceiver Station (BTS) which is consequently forwarded as an CHANNEL REQUIRED message to the Base Station Controller (BSC). If the BTS decodes some noise on the Random Access Channel (RACH) as random access by mistake (so- called ‘phantom RACH') then it is a question of pure coincidence which èstablishment cause’ the BTS thinks to have recognized. A typical invalid channel access request or phantom RACH is characterized by an IMMEDIATE ASSIGNMENT procedure (assignment of an SDCCH or TCH) which is not followed by sending an ESTABLISH INDICATION from MS to BTS. In this paper a mathematical model for evaluation of the Power RACH Busy Threshold (RACHBT) in order to guaranty in advance determined outage probability on RACH is described and discussed as well. It focuses on Global System for Mobile Communications (GSM) however the obtained results can be generalized on remaining mobile technologies (ie WCDMA and LTE).

  20. Novel secure and bandwidth efficient optical code division multiplexed system for future access networks

    Science.gov (United States)

    Singh, Simranjit

    2016-12-01

    In this paper, a spectrally coded optical code division multiple access (OCDMA) system using a hybrid modulation scheme has been investigated. The idea is to propose an effective approach for simultaneous improvement of the system capacity and security. Data formats, NRZ (non-return to zero), DQPSK (differential quadrature phase shift keying), and PoISk (polarisation shift keying) are used to get the orthogonal modulated signal. It is observed that the proposed hybrid modulation provides efficient utilisation of bandwidth, increases the data capacity and enhances the data confidentiality over existing OCDMA systems. Further, the proposed system performance is compared with the current state-of-the-art OCDMA schemes.

  1. NOTE: MRI-guided robotic system for transperineal prostate interventions: proof of principle

    Science.gov (United States)

    van den Bosch, Michiel R.; Moman, Maaike R.; van Vulpen, Marco; Battermann, Jan J.; Duiveman, Ed; van Schelven, Leonard J.; de Leeuw, Hendrik; Lagendijk, Jan J. W.; Moerland, Marinus A.

    2010-03-01

    In this study, we demonstrate the proof of principle of the University Medical Center Utrecht (UMCU) robot dedicated to magnetic resonance imaging (MRI)-guided interventions in patients. The UMCU robot consists of polymers and non-ferromagnetic materials. For transperineal prostate interventions, it can be placed between the patient's legs inside a closed bore 1.5T MR scanner. The robot can manually be translated and rotated resulting in five degrees of freedom. It contains a pneumatically driven tapping device to automatically insert a needle stepwise into the prostate using a controller unit outside the scanning room. To define the target positions and to verify the needle insertion point and the needle trajectory, a high-resolution 3D balanced steady state free precession (bSSFP) scan that provides a T2/T1-weighted contrast is acquired. During the needle insertion fast 2D bSSFP images are generated to track the needle on-line. When the target position is reached, the radiation oncologist manually places a fiducial gold marker (small seed) at this location. In total two needle trajectories are used to place all markers. Afterwards, a high-resolution 3D bSSFP scan is acquired to visualize the fiducial gold markers. Four fiducial gold markers were placed transperineally into the prostate of a patient with a clinical stage T3 prostate cancer. In the generated scans, it was possible to discriminate the patient's anatomy, the needle and the markers. All markers were delivered inside the prostate. The procedure time was 1.5 h. This study proves that MRI-guided needle placement and seed delivery in the prostate with the UMCU robot are feasible.

  2. Open Access Intellectual Property Systems: A Comparison to Commercial Solutions in Competitive Intelligence

    Directory of Open Access Journals (Sweden)

    Jan Cerny

    2016-07-01

    Full Text Available ICT/IS management plays an important role within the framework of innovation management, and one of the key elements of this role is the support of Competitive Intelligence in the context of innovation processes. The strategic information needs of innovation management are also directed towards different kinds of intellectual property (IP information entities and commercialization. The purpose of this paper is to define these entities and IP information systems as an important part of a company’s Competitive Intelligence Unit for competitor analysis and technology trends. The open access IP information systems will be analysed together with commercial solutions.. The aim of this paper is to underline the importance of open access IP systems compared to added value commercial solutions for competitive intelligence purposes for SMEs. The comparison will be carried out using examples of patent searches within a concrete dataset.

  3. Discovery of abundant, accessible hydrocarbons nearly everywhere in the solar system

    Energy Technology Data Exchange (ETDEWEB)

    Zuppero, A.

    1996-05-01

    analysis of the data gathered during the Comet Halley encounter during 1987 resulted in a body of literature asserting that all comets contain substantial percentages of hydrocarbon solids. These solids appear to have a strong similarity to petrochemicals. Arguments are made that the amount of hydrocarbon material in the accessible comets of the inner Solar system can substantially exceed the known reserves of hydrocarbons on Earth. An example is given of at least one conceptually simple method to use comet material as feedstock for space transportation schemes that can move masses through the solar system comparable to the mass carried by oil supertankers. The presentation concludes we need to send prospecting and assay probes to a sampling of the accessible comets to determine the amount of hydrocarbons and the form and location of materials needed for space transportation systems.

  4. Performance Analysis of Slotted Random Access DS-CDMA Systems with Multipacket Reception

    Institute of Scientific and Technical Information of China (English)

    ZHANGJidong; XULi; ZHENGBaoyu; XIAOHaiyong

    2004-01-01

    Multiple packets reception (MPR) is a new method to improve the network performance. If a node in the network has the capability of MPR, the node can receive multiple packets simultaneously, not to discard all the packets like the traditional method. In this paper, Bit error rate (BER) for direct-sequence spread spectrum multiple access system over Rice fading channel is considered, based on the standard Gaussian approximation, and the explicit close-form expression for BER is provided, which is expressed by a single integral. Moreover, the performance of random multiple access in the Direct-sequence code division multiple access (DS-CDMA) system with the capability of multiple packets reception is analyzed over Gaussian channel Rayleigh fading channel and Rice fad-ing channel, respectively, where the multiple packets reception is obtained by the method of match filter. The simulation results show that the MPR capability improves the throughput of DS-CDMA system greatly, compared with the conventional single packet reception. The system has the maximum throughput when signals are transmitted over the Gaussian channel. Also, the impact of Signal-to-noise ratio (SNR), channel coding and the traffic arrival model on the throughput of DS-CDMA system is given in the simulation and the analysis for the simulation results is provided.

  5. Mechatronic system for in-bore MRI-guided insertion of needles to the prostate: An in vivo needle guidance accuracy study.

    Science.gov (United States)

    Cepek, Jeremy; Lindner, Uri; Ghai, Sangeet; Louis, Alyssa S; Davidson, Sean R H; Gertner, Mark; Hlasny, Eugen; Sussman, Marshall S; Fenster, Aaron; Trachtenberg, John

    2015-07-01

    To present our experiences in initial clinical evaluation of a novel mechatronic system for in-bore guidance of needles to the prostate for MRI-guided prostate interventions in 10 patients. We report accuracy of this device in the context of focal laser ablation therapy for localized prostate cancer. An MRI-compatible needle guidance device was developed for transperineal prostate interventions. Ten patients underwent MRI-guided focal laser ablation therapy with device-mediated laser fiber delivery. We recorded needle guidance error and needle delivery time. A total of 37 needle insertions were evaluated. Median needle guidance error was 3.5 mm (interquartile range, 2.1-5.4 mm), and median needle delivery time was 9 min (interquartile range, 6.5-12 min). This system provides a reliable method of accurately aligning needle guides for in-bore transperineal needle delivery to the prostate. © 2014 Wiley Periodicals, Inc.

  6. A Novel Medium Access Control for Ad hoc Networks Based on OFDM System

    Institute of Scientific and Technical Information of China (English)

    YU Yi-fan; YIN Chang-chuan; YUE Guang-xin

    2005-01-01

    Recently, hosts of Medium Access Control (MAC) protocols for Ad hoc radio networks have been proposed to solve the hidden terminal problem and exposed terminal problem. However most of them take into no account the interactions between physical (PHY) system and MAC protocol. Therefore, the current MAC protocols are either inefficient in the networks with mobile nodes and fading channel or difficult in hardware implementation. In this paper, we present a novel media access control for Ad hoc networks that integrates a media access control protocol termed as Dual Busy Tone Multiple Access (DBTMA) into Orthogonal Frequency Division Multiplexing (OFDM) system proposed in IEEE 802.11a standard. The analysis presented in the paper indicates that the proposed MAC scheme achieves performance improvement over IEEE 802.11 protocol about 25%~80% especially in the environment with high mobility and deep fading. The complexity of the proposed scheme is also lower than other implementation of similar busy tone solution. Furthermore, it is compatible with IEEE 802.11a networks.

  7. Return Migrants’ Experience of Access to Care in Corrupt Healthcare Systems: The Bosnian Example

    Science.gov (United States)

    Neerup Handlos, Line; Fog Olwig, Karen; Bygbjerg, Ib Christian; Norredam, Marie

    2016-01-01

    Equal and universal access to healthcare services is a core priority for a just health system. A key societal determinant seen to create inequality in access to healthcare is corruption in the healthcare system. How return migrants’ access to healthcare is affected by corruption is largely unstudied, even though return migrants may be particularly vulnerable to problems related to corruption due to their period of absence from their country of origin. This article investigates how corruption in the healthcare sector affects access to healthcare for refugees who repatriated to Bosnia, a country with a high level of corruption, from Denmark, a country with a low level of corruption. The study is based on 18 semi-structured interviews with 33 refugees who returned after long-term residence in Denmark. We found that the returned refugees faced greater problems with corruption than was the case for those who had not left the country, as doctors considered them to be better endowed financially and therefore demanded larger bribes from them than they did from those who had remained in Bosnia. Moreover, during their stay abroad the returnees had lost the connections that could have helped them sidestep the corruption. Returned refugees are thus particularly vulnerable to the effects of corruption. PMID:27657096

  8. Preconceptual systems and equipment for plugging of man-made accesses to a repository in basalt

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, C.L.; O' Rourke, J.E.; Allirot, D.; O' Connor, K.

    1980-09-01

    This report presents results of a study leading to preconceptual designs for plugging boreholes, shafts, and tunnels to a nuclear waste repository in basalt. Beginning design criteria include a list of preferred plug materials and plugging machines that were selected to suit the environmental conditions, and depths, diameters, and orientations of the accesses to a nuclear waste repository in the Columbia River basalts located in eastern Washington State. The environmental conditions are described. The fiscal year 1979-1980 Task II work is presented in two parts: preliminary testing of materials for plugging of man-made accesses to a repository in basalt (described in a separate report); and preconceptual systems and equipment for plugging of man-made accesses to a repository in basalt (described in this report). To fulfill the scope of the Task II work, Woodward-Clyde Consultants (WCC) was requested to: provide preconceptual systems for plugging boreholes, tunnels, and shafts in basalt; describe preconceptual borehole plugging equipment for placing the selected materials in man-made accesses; utilize the quality assurance program, program plan and schedule, and work plans previously developed for Task II; and prepare a preliminary report.

  9. Return Migrants’ Experience of Access to Care in Corrupt Healthcare Systems: The Bosnian Example

    Directory of Open Access Journals (Sweden)

    Line Neerup Handlos

    2016-09-01

    Full Text Available Equal and universal access to healthcare services is a core priority for a just health system. A key societal determinant seen to create inequality in access to healthcare is corruption in the healthcare system. How return migrants’ access to healthcare is affected by corruption is largely unstudied, even though return migrants may be particularly vulnerable to problems related to corruption due to their period of absence from their country of origin. This article investigates how corruption in the healthcare sector affects access to healthcare for refugees who repatriated to Bosnia, a country with a high level of corruption, from Denmark, a country with a low level of corruption. The study is based on 18 semi-structured interviews with 33 refugees who returned after long-term residence in Denmark. We found that the returned refugees faced greater problems with corruption than was the case for those who had not left the country, as doctors considered them to be better endowed financially and therefore demanded larger bribes from them than they did from those who had remained in Bosnia. Moreover, during their stay abroad the returnees had lost the connections that could have helped them sidestep the corruption. Returned refugees are thus particularly vulnerable to the effects of corruption.

  10. Brain unidentified bright objects ("UBO") in systemic lupus erythematosus: sometimes they come back. A study of microembolism by cMRI and Transcranial Doppler ultrasound.

    Science.gov (United States)

    Bortoluzzi, A; Padovan, M; Azzini, C; De Vito, A; Trotta, F; Govoni, M

    2016-02-01

    The objectives of this report are to assess the occurrence of microembolic signals (MES) detected by transcranial Doppler ultrasound (TCD) in systemic lupus erythematosus (SLE) patients with (NPSLE) and without (SLE) neuropsychiatric involvement, and to verify the correlation between MES, clinical characteristics, especially the patent foramen ovale (PFO), and the presence of punctuate T2-hyperintense white matter lesions (WMHLs) detected by conventional magnetic resonance imaging (cMRI). A TCD registration to detect MES from the middle cerebral artery was carried out in SLE and NPSLE patients after exclusion of aortic and/or carotid atheromatous disease. In all patients conventional brain magnetic resonance imaging (cMRI) and transesophageal echocardiography were performed. Patients were stratified in two groups, with and without WMHLs, and compared. Twenty-three SLE patients (16 NPSLE and seven SLE) were enrolled in the study. Overall MES were detected in 12 patients (52.1%), WHMLs were detectable in 15 patients (13 NPSLE and two SLE) while eight patients had normal cMRI (three NPSLE and five SLE). Matching TCD ultrasound and neuroimaging data, MES were detected in 10 (nine NPSLE and one SLE) out of 15 patients with WHMLs and in only two out of eight patients (two NPSLE and six SLE) with normal cMRI, both with NP involvement. A PFO was confirmed in all cases of MES detection. MES are frequent findings in SLE patients, especially in those with focal WMHLs detected by cMRI and correlating with PFO. These findings should be taken into account and suggest caution in the interpretation of cMRI pictures along with a careful evaluation of MES in patients with cMRI abnormalities that should be included in the workup of SLE patients. © The Author(s) 2015.

  11. Design of a conduction-cooled 9.4 T REBCO magnet for whole-body MRI systems

    Science.gov (United States)

    Miyazaki, Hiroshi; Iwai, Sadanori; Otani, Yasumi; Takahashi, Masahiko; Tosaka, Taizo; Tasaki, Kenji; Nomura, Shunji; Kurusu, Tsutomu; Ueda, Hiroshi; Noguchi, So; Ishiyama, Atsushi; Urayama, Shinichi; Fukuyama, Hidenao

    2016-10-01

    A project on the development of REBa2Cu3O7-δ (REBCO) magnets for ultra-high-field magnetic resonance imaging (MRI) was started in 2013. Since REBCO-coated conductors feature high mechanical strength under tensile stress and high critical current density, use of REBCO coils would allow superconducting magnets to be made smaller and lighter than conventional ones. In addition, a conduction-cooled superconducting magnet is simpler to use than one cooled by a liquid helium bath because the operation and maintenance of the cryogenic system become simpler, without the need to handle cryogenic fluid. Superconducting magnets for MRI require homogeneous, stable magnetic fields. The homogeneity of the magnetic field is highly dependent on the coil shape and position. Moreover, in REBCO magnets, the screening-current-induced magnetic field, which changes the magnetic field distribution of the magnet, is one of the critical issues. In order to evaluate the magnetic field homogeneity and the screening-current-induced magnetic field, a 1 T model magnet and some test coils were fabricated. From an evaluation of the 1 T model magnet, it was found that the main reason for magnetic field inhomogeneity was the tolerances in the z-axis positions of the coils, and therefore, it is important to control the gap between the single pancakes. In addition, we have already demonstrated the generation of an 8.27 T central magnetic field at 10 K with a small test coil. The screening-current-induced magnetic field was 0.43 T and was predictable by using an electromagnetic field simulation program. These results were reflected in the design of a conduction-cooled 9.4 T REBCO magnet for whole-body MRI systems. The magnet was composed of six main coils and two active shield coils. The total conductor length was 581 km, and the stored energy was 293 kJ. The field inhomogeneity was 24 ppm peak to peak and 3 ppm volume-root-mean-square (VRMS) for a 500 mm diameter spherical volume (DSV). The axial

  12. Retention in a public health care system with free access to treatment

    DEFF Research Database (Denmark)

    Helleberg, Marie; Engsig, Frederik N; Kronborg, Gitte;

    2012-01-01

    OBJECTIVE:: We aimed to assess retention of HIV infected individuals in the Danish health care system over a 15-year period. METHODS:: Loss to follow-up (LTFU) was defined as 365 days without contact to the HIV care system. Data were obtained from the nationwide Danish HIV Cohort study, The Danis......, especially after initiation of HAART. Absence from HIV care is associated with increased mortality. We conclude that high rates of retention can be achieved in a health care system with free access to treatment and is associated with a favorable outcome....

  13. Face Recognition Based Door Lock System Using Opencv and C# with Remote Access and Security Features

    Directory of Open Access Journals (Sweden)

    Prathamesh Timse

    2014-04-01

    Full Text Available This paper investigates the accuracy and effectiveness of the face detection and recognition algorithms using OpenCV and C# computer language. The adaboost algorithm [2] is used for face detection and PCA algorithm[1] is used for face recognition. This paper also investigates the robustness of the face recognition system when an unknown person is being detected, wherein the system will send an email to the owner of the system using SMTP [7]. The door lock can also be accessed remotely from any part of the world by using a Dropbox [8] account.

  14. MRI Findings In Dengue Encephalitis

    Directory of Open Access Journals (Sweden)

    Ashraf V.V

    2004-01-01

    Full Text Available Neurological manifestations are rare in dengue fever. Two cases with encephalopathy and systemic features of dengue fever with abnormal CSF and MR imaging are reported. Striking MRI finding was bilateral symmetrical thalamic lesions similar to those reported in Japanese encephalitis. This report highlights that MRI findings can be similar in dengue and Japanese encephalitis.

  15. Can a self-referral system help improve access to psychological treatments?

    Science.gov (United States)

    Brown, June S L; Boardman, Jed; Whittinger, Naureen; Ashworth, Mark

    2010-05-01

    Referrals for psychological treatment have been problematic for many years. Even though GPs have attempted to limit access into the small psychological treatment services, long waiting lists have developed which have deterred referrals and deferred psychological care. GPs have understandably been frustrated. In addition, the consultation rate for psychological problems is low when compared with the rate of identified mental health problems in population surveys. Possible reasons include patients' failure to recognise the problem as psychological and thus not consulting one's GP, and/or the problem not being detected by the GP. While a self-referral system may be seen as a way of trying to allow non-consulters to receive treatment, this has been viewed with some scepticism since it may allow the 'worried well' to access already limited services. However, a study has shown that those self-referring to advertised psychological workshops had high levels of psychological morbidity and also were more representative of the population, in terms of ethnicity, than GP referrals. The government has set up the Increasing Access to Psychological Therapies (IAPT) programme to address some of the service shortfalls by expanding the provision of psychological therapists. Notably, the IAPT programme is allowing self-referrals such that any member of the public can access the service directly, bypassing general practice. Although not available at all the sites, this represents a radical shift from the present system in which access to talking therapy is generally only available through direct referral by the GP. The implications of this new development are discussed.

  16. Security Camera System can be access into mobile with internet from remote place

    Directory of Open Access Journals (Sweden)

    Dr. Khanna SamratVivekanand Omprakash

    2012-01-01

    Full Text Available This paper represents how camera can captured the images and video into the database and then it may transformed to the mobile with help of Internet. Developing mobile applications how the data can be viewed on the mobile from the remote place. By assigning real IP to the storage device from ISP and connected to the internet . Developing mobile applications on windows mobile which runs only on the windows mobile . Wireless camera in terms of 4 , 8, 12, 16 are connected with the system. Windows based application develop for 4 , 8 , 12,16 channels to see at a time on desktop computer . The PC is connected with internet and having Client server application which is connected to the Windows Web hosting Server through the internet. With the help of ISP server we can assign IP to the Window Web Server with domain name . Domain name will be access from the world. By developing mobile applications on web we can access it on mobile . Separate setup of windows .exe develop for the Windows Mobile phone to access the information from the server. Client setup can be installed on the mobile and it fetches the data from server and server is based on real IP with domain name and connected with Internet . Digital Wireless cameras are connected & data is stored in Digital Video Recorder having 1 Terabyte of hard disk with different channel like 4, 8, 12,16. We can see Video output in mobile by installing the client setup or by accessing directly from web browser which supports the application for mobile. The beauty of this software is that we can access security camera system into the mobile with internet from remote place.

  17. A fuzzy expert system to Trust-Based Access Control in crowdsourcing environments

    Directory of Open Access Journals (Sweden)

    Olusegun Folorunso

    2015-07-01

    Full Text Available Crowdsourcing has been widely accepted across a broad range of application areas. In crowdsourcing environments, the possibility of performing human computation is characterized with risks due to the openness of their web-based platforms where each crowd worker joins and participates in the process at any time, causing serious effect on the quality of its computation. In this paper, a combination of Trust-Based Access Control (TBAC strategy and fuzzy-expert systems was used to enhance the quality of human computation in crowdsourcing environment. A TBAC-fuzzy algorithm was developed and implemented using MATLAB 7.6.0 to compute trust value (Tvalue, priority value as evaluated by fuzzy inference system (FIS and finally generate access decision to each crowd-worker. In conclusion, the use of TBAC is feasible in improving quality of human computation in crowdsourcing environments.

  18. A web accessible scientific workflow system for vadoze zone performance monitoring: design and implementation examples

    Science.gov (United States)

    Mattson, E.; Versteeg, R.; Ankeny, M.; Stormberg, G.

    2005-12-01

    Long term performance monitoring has been identified by DOE, DOD and EPA as one of the most challenging and costly elements of contaminated site remedial efforts. Such monitoring should provide timely and actionable information relevant to a multitude of stakeholder needs. This information should be obtained in a manner which is auditable, cost effective and transparent. Over the last several years INL staff has designed and implemented a web accessible scientific workflow system for environmental monitoring. This workflow environment integrates distributed, automated data acquisition from diverse sensors (geophysical, geochemical and hydrological) with server side data management and information visualization through flexible browser based data access tools. Component technologies include a rich browser-based client (using dynamic javascript and html/css) for data selection, a back-end server which uses PHP for data processing, user management, and result delivery, and third party applications which are invoked by the back-end using webservices. This system has been implemented and is operational for several sites, including the Ruby Gulch Waste Rock Repository (a capped mine waste rock dump on the Gilt Edge Mine Superfund Site), the INL Vadoze Zone Research Park and an alternative cover landfill. Implementations for other vadoze zone sites are currently in progress. These systems allow for autonomous performance monitoring through automated data analysis and report generation. This performance monitoring has allowed users to obtain insights into system dynamics, regulatory compliance and residence times of water. Our system uses modular components for data selection and graphing and WSDL compliant webservices for external functions such as statistical analyses and model invocations. Thus, implementing this system for novel sites and extending functionality (e.g. adding novel models) is relatively straightforward. As system access requires a standard webbrowser

  19. fMRI investigation of the effect of local and systemic lidocaine on noxious electrical stimulation-induced activation in spinal cord.

    Science.gov (United States)

    Zhao, Fuqiang; Williams, Mangay; Welsh, Denise C; Meng, Xiangjun; Ritter, Amy; Abbadie, Catherine; Cook, Jacquelynn J; Reicin, Alise S; Hargreaves, Richard; Williams, Donald S

    2009-09-01

    Spinal cord fMRI offers an excellent opportunity to quantify nociception using neuronal activation induced by painful stimuli. Measurement of the magnitude of stimulation-induced activation, and its suppression with analgesics can provide objective measures of pain and efficacy of analgesics. This study investigates the feasibility of using spinal cord fMRI in anesthetized rats as a pain assay to test the analgesic effect of locally and systemically administered lidocaine. Blood volume (BV)-weighted fMRI signal acquired after intravenous injection of ultrasmall superparamagnetic iron oxide (USPIO) particles was used as an indirect readout of the neuronal activity. Transcutaneous noxious electrical stimulation was used as the pain model. BV-weighted fMRI signal could be robustly quantified on a run-by-run basis, opening the possibility of measuring pharmacodynamics (PD) of the analgesics with a temporal resolution of approximately 2 min. Local administration of lidocaine was shown to ablate all stimulation-induced fMRI signals by the total blockage of peripheral nerve transmission, while the analgesic effect of systemically administered lidocaine was robustly detected after intravenous infusion of approximately 3mg/kg, which is similar to clinical dosage for human. This study establishes spinal cord fMRI as a viable assay for analgesics. With respect to the mode of action of lidocaine, this study suggests that systemic lidocaine, which is clinically used for the treatment of neuropathic pain, and believed to only block the peripheral nerve transmission of abnormal neural activity (ectopic discharge) originating from the damaged peripheral nerves, also blocks the peripheral nerve transmission of normal neural activity induced by transcutaneous noxious electrical stimulation.

  20. Low-Cost Encoding Device for Optical Code Division Multiple Access System

    OpenAIRE

    Mohammad S. Ab-Rahman; Boonchuan Ng; Norshilawati M. Ibrahim; Sahbudin Shaari

    2009-01-01

    Problem statement: Instead of using Fiber Bragg Grating (FBG) to develop the coded spectrums, which consist of expensive elements, the grating also are highly sensitive to environmental changes and this will contribute to the increment of capital and operational expenditures (CAPEX and OPEX). Approach: This study presented the development of low-cost 16-ports encoding device for Optical Code Division Multiple Access (OCDMA) systems based on Arrayed Waveguide Grating (AWG) devices and optical ...

  1. Osiris: accessible and reproducible phylogenetic and phylogenomic analyses within the Galaxy workflow management system

    OpenAIRE

    2014-01-01

    Background Phylogenetic tools and ‘tree-thinking’ approaches increasingly permeate all biological research. At the same time, phylogenetic data sets are expanding at breakneck pace, facilitated by increasingly economical sequencing technologies. Therefore, there is an urgent need for accessible, modular, and sharable tools for phylogenetic analysis. Results We developed a suite of wrappers for new and existing phylogenetics tools for the Galaxy workflow management system that we call Osiris. ...

  2. An Acquisition Performance Analysis of DS-MC-CDMA System under Multiple Access Interference Conditions

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Multi-Access Interference's (MAI's) effect on parallel acquisition performance of DS-Multi-carrier CDMA system under the typical indoor radio channel is discussed in the paper. Moreover, a comparison of acquisition performance impairment produced by the MAI in DS-MC-CDMA and DS-Single-carrier CDMA is also made. Results are given in terms of average acquisition time obtained by means of simulations and theory analysis.

  3. Distributed Multi-Sensor Real-Time Building Environmental Parameters Monitoring System with Remote Data Access

    Directory of Open Access Journals (Sweden)

    Beinarts Ivars

    2014-12-01

    Full Text Available In this paper the advanced monitoring system of multiple environmental parameters is presented. The purpose of the system is a long-term estimation of energy efficiency and sustainability for the research test stands which are made of different building materials. Construction of test stands, and placement of main sensors are presented in the first chapter. The structure of data acquisition system includes a real-time interface with sensors and a data logger that allows to acquire and log data from all sensors with fixed rate. The data logging system provides a remote access to the processing of the acquired data and carries out periodical saving at a remote FTP server using an Internet connection. The system architecture and the usage of sensors are explained in the second chapter. In the third chapter implementation of the system, different interfaces of sensors and energy measuring devices are discussed and several examples of data logger program are presented. Each data logger is reading data from analog and digital channels. Measurements can be displayed directly on a screen using WEB access or using data from FTP server. Measurements and acquired data graphical results are presented in the fourth chapter in the selected diagrams. The benefits of the developed system are presented in the conclusion.

  4. Time resolved flow quantification with MRI using phase methods: a linear systems approach.

    Science.gov (United States)

    Peeters, F; Luypaert, R; Eisendrath, H; Osteaux, M

    1995-03-01

    Phase-related unsteady (pulsatile) flow effects in MRI have been studied by means of linear response theory. These flow effects can be described in the frequency domain: the influence of the gradients on the phase shift is described by a transfer function, the spectrum of the gradient being the determining factor. An analysis of this transfer function is shown to provide information about the process of flow encoding: instant of encoding, induced distortions and how they are related to the gradient waveform. The connection with the traditional description in terms of the gradient moment expansion has also been investigated and clarified. This approach was applied to study the response of two time-resolved flow quantification techniques (Fourier flow method and phase mapping) by analyzing their amplitude and phase transfer functions. By simulation it is shown that a better interpretation of the measured velocity waveform is obtained and that Fourier analysis in combination with a correction by the inverse transfer function results in an accurate reconstruction of the velocity waveform studied.

  5. Breast MRI scan

    Science.gov (United States)

    MRI - breast; Magnetic resonance imaging - breast; Breast cancer - MRI; Breast cancer screening - MRI ... radiologist) see some areas more clearly. During the MRI, the person who operates the machine will watch ...

  6. MRI Safety during Pregnancy

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z MRI Safety During Pregnancy Magnetic resonance imaging (MRI) Illness ... during the exam? Contrast material MRI during pregnancy Magnetic resonance imaging (MRI) If you are pregnant and your doctor ...

  7. MRI (Magnetic Resonance Imaging)

    Science.gov (United States)

    ... and Procedures Medical Imaging MRI (Magnetic Resonance Imaging) MRI (Magnetic Resonance Imaging) Share Tweet Linkedin Pin it More sharing options ... usually given through an IV in the arm. MRI Research Programs at FDA Magnetic Resonance Imaging (MRI) ...

  8. MRI of the Chest

    Medline Plus

    Full Text Available ... the limitations of MRI of the Chest? What is MRI of the Chest? Magnetic resonance imaging (MRI) ... ray, CT and ultrasound. top of page How is the procedure performed? MRI examinations may be performed ...

  9. Frequency-selective design of wireless power transfer systems for controlled access applications

    Science.gov (United States)

    Maschino, Tyler Stephen

    Wireless power transfer (WPT) has become a common way to charge or power many types of devices, ranging from cell phones to electric toothbrushes. WPT became popular through the introduction of a transmission mode known as strongly coupled magnetic resonance (SCMR). This means of transmission is non-radiative and enables mid-range WPT. Shortly after the development of WPT via SCMR, a group of researchers introduced the concept of resonant repeaters, which allows power to hop from the source to the device. These repeaters are in resonance with the WPT system, which enables them to propagate the power wirelessly with minimal losses to the environment. Resonant repeaters have rekindled the dream of ubiquitous wireless power. Inherent risks come with the realization of such a dream. One of the most prominent risks, which we set out in this thesis to address, is that of accessibility to the WPT system. We propose the incorporation of a controlled access schema within a WPT system to prevent unwarranted use of wireless power. Our thesis discusses the history of electromagnetism, examines the inception of WPT via SCMR, evaluates recent developments in WPT, and further elaborates on the controlled access schema we wish to contribute to the field.

  10. GAPforAPE: an augmented browsing system to improve Web 2.0 accessibility

    Science.gov (United States)

    Mirri, Silvia; Salomoni, Paola; Prandi, Catia; Muratori, Ludovico Antonio

    2012-09-01

    The Web 2.0 evolution has spread more interactive technologies which affected accessibility for users who navigate the Web by using assistive technologies. In particular, the partial download of new data, the continuous refreshing, and the massive use of scripting can represent significant barriers especially for people with visual impairments, who enjoy the Web by means of screen readers. On the other hand, such technologies can be an opportunity, because they can provide a new means of transcoding Web content, making the Web more accessible. In this article we present GAPforAPE, an augmented browsing system (based on Web browsers extensions) which offers a user's profiling system and transcodes Web content according to constrains declared by users: the same Web page is provided to any user, but GAPforAPE computes adequate customizations, by exploiting scripting technologies which usually affect Web pages accessibility. GAPforAPE imitates screen readers behavior: it applies a specific set of transcoding scripts devoted to a given Web site, when available, and a default set of transcoding operations otherwise. The continuous and quick evolution of the Web has shown that a crowdsourcing system is a desirable solution, letting the transcoding scripts evolve in the same way.

  11. Smart Bank Locker Access System Using Iris ,Fingerprints,Face Recognization Along With Password Authentication And Billing System

    Directory of Open Access Journals (Sweden)

    Asst.Prof.T.A.More

    2015-03-01

    Full Text Available In today's modern world, security plays an important role. For that purpose, we proposed advance security systems for banking locker system and the bank customers. This specialized security is proposed through four different modules in combination i.e. face detection technique, Password verification, finger prints and Iris verification .All these steps are followed in the sequence if anything goes wrong he or she is unable to access the system. We are also providing some additional billing with it i.e. it will always for after 1 transaction. It will give the intimation of first transaction is complete and you are left with prescribed number transaction mentioned in system.

  12. Global system data bus using the Digital Autonomous Terminal Access Communication protocol

    Science.gov (United States)

    Holmes, David C. E.

    1986-01-01

    Modern digital avionic systems with distributed processing require networking to connect the many elements. Digital Autonomous Terminal Access Communication (DATAC) is one of many such networks. DATAC has been implemented on the Transport Systems Research Vehicle (TSRV), a Boeing 737 aircraft operated by the National Aeronautics and Space Administration's Advanced Transport Operating Systems Program Office (ATOPS). This paper presents the TSRV implementation of the DATAC bus, a description of the DATAC system, a synchronization mechanism, details of data flow throughout the system, and a discussion of the modes available with DATAC. Numerous flight tests have been conducted using DATAC as the only means of communication between systems with outstanding results. DATAC is now an integral part of the TSRV and is expected to satisfy near term as well as future requirements for growth and flexibility.

  13. Predictive value of semi-quantitative MRI-based scoring systems for future knee replacement: data from the osteoarthritis initiative

    Energy Technology Data Exchange (ETDEWEB)

    Hafezi-Nejad, Nima; Eng, John; Demehri, Shadpour [Johns Hopkins University School of Medicine, Musculoskeletal Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Zikria, Bashir [Johns Hopkins University, Department of Orthopedic Surgery, Baltimore, MD (United States); Carrino, John A. [Hospital for Special Surgery, Department of Radiology and Imaging, New York, NY (United States)

    2015-11-15

    To evaluate, in a confirmatory fashion, whether baseline and change from baseline to 24-month follow-up in cartilage damage, bone marrow lesions and meniscal damage are predictors of knee replacement (KR) in subjects with a high risk of osteoarthritis (OA), independent of the level of physical activity, symptom severity and radiographic abnormalities. Data from the Osteoarthritis Initiative's (OAI) baseline and 24-month follow-up knee MRIs of 115 patients (age range: 45-78 years; 48 % female; BMI: 20.9-48.7) were analyzed. Cartilage, bone marrow and menisci were semi-quantitatively scored according to the Whole-Organ Magnetic Resonance Imaging Score (WORMS) and Boston-Leeds Osteoarthritis Knee Score (BLOKS) systems in all compartments. Baseline and 24-month interval changes in structural tissue damage assessed by BLOKS and WORMS were used as predictors of KR independent of clinical and radiographic parameters using Cox hazard analysis. Adjustments were performed for age, gender, BMI and physical activity (Physical Activity Scale for the Elderly: PASE), Western Ontario and McMaster Questionnaire (WOMAC) total score and radiographic Kellgren-Lawrence (KL) score. BLOKS and WORMS baseline cartilage scores were predictors of KR independent of the PASE, WOMAC and KL score. One score increase in the average baseline BLOKS full-thickness cartilage defect score was associated with a [hazard ratio (95 % CI)] 13.55 (3.61-50.89) times greater risk of KR independent of the PASE, WOMAC and KL score. Net reclassification improvements (NRIs) of the additional evaluation of 24-month follow-up MRI scores and assessment of changes were not significant for prediction of KR (NRI range: - 7.23 - 24.8 %). The BLOKS cartilage score for full-thickness cartilage defects had the highest hazard for KR. Follow-up MRI changes in structural tissue damage, detected by BLOKS and WORMS cartilage, bone marrow or meniscus scores (up to 24 months) had no significant predictive value in addition

  14. Design of a loop resonator with a split-ring-resonator (SRR) for a human-body coil in 3 T MRI systems

    Science.gov (United States)

    Son, Hyeok Woo; Cho, Young Ki; Kim, Byung Mun; Back, Hyun Man; Yoo, Hyoungsuk

    2016-04-01

    A new radio-frequency (RF) resonator for Nuclear Magnetic Resonance (NMR) imaging at clinical magnetic resonance imaging (MRI) systems is proposed in this paper. An approach based on the effects of the properties of metamaterials in split-ring resonators (SRRs) is used to design a new loop resonator with a SRR for NMR imaging. This loop resonator with a SRR is designed for NMR imaging at 3 T MRI systems. The 3D electromagnetic simulation was used to optimize the design of the proposed RF resonator and analyze it's performance at 3 T MRI systems. The proposed RF resonator provides strong penetrating magnetic fields at the center of the human phantom model, approximately 10%, as compared to the traditional loop-type RF resonator used for NMR imaging at clinical MRI systems. We also designed an 8-channel body coil for human-body NMR imaging by using the proposed loop resonator with a SRR. This body coil also produces more homogeneous and highly penetrating magnetic fields into the human phantom model.

  15. A study of usefulness for the plan based on only MRI using ViewRay MRIdian system

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Chang Woo; Lee, Ho Jin; An, Beom Seok; Kim, Chan Young; Lee, Je Hee [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2015-12-15

    By comparing a CT fusion plan based on MRI with a plan based on only MRI without CT, we intended to study usefulness of a plan based on only MRI. And furthermore, we intended to realize a realtime MR-IGRT by MRI image without CT scan during the course of simulation, treatment planning, and radiation treatment. BBB CT (Brilliance Big Bore CT, 16slice, Philips), Viewray MRIdian system (Viewray, USA) were used for CT and MR simulation and Treatment plan of 11 patients (1 Head and Neck, 5 Breast, 1 Lung, 3 Liver, 1 Prostate). When scanning for treatment, Free Breathing was enacted for Head and Neck, Breast, Prostate and Inhalation Breathing Holding for Lung and Liver. Considering the difference of size between CT and Viewray, the patient's position and devices were in the same condition. Using Viewray MRIdian system, two treatment plans were established. The one was CT fusion treatment plan based on MR image. Another was MR treatment plan including electron density that [ICRU 46] recommend for Lung, Air and Bone. For Head and Neck, Breast and Prostate, IMRT was established and for Lung and Liver, Gating treatment plan was established. PTV's Homogeneity Index(HI) and Conformity Index(CI) were use to estimate the treatment plan. And DVH and dose difference of each PTV and OAR were compared to estimate the treatment plan. Between the two treatment plan, each difference of PTV's HI value is 0.089% (Head and Neck), 0.26% (Breast), 0.67% (Lung), 0.2% (Liver), 0.4% (Prostate) and in case of CI, 0.043% (Head and Neck), 0.84% (Breast), 0.68% (Lung), 0.46% (Liver), 0.3% (Prostate). As showed above, it is on Head and Neck that HI and CI's difference value is smallest. Each difference of average dose on PTV is 0.07 Gy (Head and Neck), 0.29 Gy (Breast), 0.18 Gy (Lung), 0.3 Gy (Liver), 0.18 Gy (Prostate). And by percentage, it is 0.06% (Head and Neck), 0.7% (Breast), 0.29% (Lung), 0.69% (Liver), 0.44% (Prostate). Likewise, All is under 1%. In Head and Neck

  16. The optimal access system for future far-offshore wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Obdam, T.S.; Rademakers, L.W.M.M.; Savenije, L.B. [ECN Wind Energy, Petten (Netherlands)

    2013-12-15

    Operation and maintenance (O and M) of offshore wind turbines is one of the main cost drivers of offshore wind energy. One of the aspects critical for an efficient and cost-effective O and M strategy is the selection of the access system which is used to transfer technicians and, optionally, small spare parts. Currently, most offshore wind farms are located close to shore, and their size is relatively small. For these farms the typical access system consists of catamaran-like workboats, which are used to transfer both technicians and small spare parts. As wind farms move further offshore this O and M concept might no longer be cost-effective. Currently, different alternative O and M concepts are being considered for the future far-offshore sites. In this paper an extensive and holistic comparison of different O and M concepts including different access system solutions is presented. This analysis has been performed using the OMCECalculator, ECN's software for advanced O and M cost modelling. Different sites have been considered, which are typical for the future offshore wind farms that will be commissioned during the next five years. The results of the performed analyses indicate that when moving further offshore harbour-based O and M strategies are no longer economical, even when helicopters are added to the mix. Looking at farm-based O and M concepts a supply vessel with a compensated access gangway offers great potential. However, the calculations also indicate that its ability to transfer small spare parts, in addition to technicians, is crucial.

  17. The optimal access system for future far-offshore wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Obdam, T.S.; Rademakers, L.W.M.M.; Savenije, L.B. [ECN Wind Energy, Petten (Netherlands)

    2013-12-15

    Operation and maintenance (O and M) of offshore wind turbines is one of the main cost drivers of offshore wind energy. One of the aspects critical for an efficient and cost-effective O and M strategy is the selection of the access system which is used to transfer technicians and, optionally, small spare parts. Currently, most offshore wind farms are located close to shore, and their size is relatively small. For these farms the typical access system consists of catamaran-like workboats, which are used to transfer both technicians and small spare parts. As wind farms move further offshore this O and M concept might no longer be cost-effective. Currently, different alternative O and M concepts are being considered for the future far-offshore sites. In this paper an extensive and holistic comparison of different O and M concepts including different access system solutions is presented. This analysis has been performed using the OMCECalculator, ECN's software for advanced O and M cost modelling. Different sites have been considered, which are typical for the future offshore wind farms that will be commissioned during the next five years. The results of the performed analyses indicate that when moving further offshore harbour-based O and M strategies are no longer economical, even when helicopters are added to the mix. Looking at farm-based O and M concepts a supply vessel with a compensated access gangway offers great potential. However, the calculations also indicate that its ability to transfer small spare parts, in addition to technicians, is crucial.

  18. Case Study of Ecstatic Meditation: fMRI and EEG Evidence of Self-Stimulating a Reward System

    Directory of Open Access Journals (Sweden)

    Michael R. Hagerty

    2013-01-01

    Full Text Available We report the first neural recording during ecstatic meditations called jhanas and test whether a brain reward system plays a role in the joy reported. Jhanas are Altered States of Consciousness (ASC that imply major brain changes based on subjective reports: (1 external awareness dims, (2 internal verbalizations fade, (3 the sense of personal boundaries is altered, (4 attention is highly focused on the object of meditation, and (5 joy increases to high levels. The fMRI and EEG results from an experienced meditator show changes in brain activity in 11 regions shown to be associated with the subjective reports, and these changes occur promptly after jhana is entered. In particular, the extreme joy is associated not only with activation of cortical processes but also with activation of the nucleus accumbens (NAc in the dopamine/opioid reward system. We test three mechanisms by which the subject might stimulate his own reward system by external means and reject all three. Taken together, these results demonstrate an apparently novel method of self-stimulating a brain reward system using only internal mental processes in a highly trained subject.

  19. Conduction cooled magnet design for 1.5 T, 3.0 T and 7.0 T MRI systems

    Science.gov (United States)

    Baig, Tanvir; Yao, Zhen; Doll, David; Tomsic, Michael; Martens, Michael

    2014-12-01

    Main magnets for magnetic resonance imaging (MRI) are largely constructed with low temperature superconducting material. Most commonly used superconductors for these magnets are niobium-titanium (NbTi). Such magnets are operated at 4.2 K by being immersed in a liquid helium bath for long time operation. As the cost of liquid helium has increased threefold in the last decade and the market for MRI systems is on average increasing by more than 7% every year, there is a growing demand for an alternative to liquid helium. Superconductors such as magnesium-diboride (MgB2) and niobium-tin (Nb3Sn) demonstrate superior current carrying quality at higher critical temperatures than 4.2 K. In this article, electromagnetic designs for conduction cooled main magnets over the range of medium field strengths (1.5 T) to ultrahigh field strengths (7.0 T) are presented. These designs are achieved by an improved functional approach coming from a series of developments by the present research group and using properties of the state-of-the-art second generation MgB2 wires and Nb3Sn wires developed by Hyper Tech Research Inc. The MgB2 magnet designs operated at different field strengths demonstrate excellent homogeneity and shielding properties at an operating temperature of 10 K. At ultrahigh field, the high current density on Nb3Sn allowed by the larger magnetic field on wire helps to reduce the superconductor volume in comparison with high field NbTi magnet designs. This allows for a compact magnet design that can operate at a temperature of 8 K. Overall, the designs created show promise in the development of conduction cooled dry magnets that would reduce dependence on helium.

  20. MRI in Japanese encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology; Misra, U.K. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Neurology; Kalita, J. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Neurology; Salwani, V. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology; Gupta, R.K. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology; Gujral, R. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology

    1997-03-01

    We document the MRI features in seven patients with Japanese encephalitis. MRI was carried out on a 1.5 T system within 10-60 days of onset. In all the patients MRI revealed bilateral thalamic lesions, haemorrhagic in five. Signal changes were present in the cerebrum in four patients, the midbrain and cerebellum in three each, the pons in two and the basal ganglia in one. The lesions were haemorrhagic in three of the four patients with lesions in the cortex, two of the three with lesions in the midbrain and cerebellum, but the pontine lesions were haemorrhagic in both patients. Spinal cord involvement was seen in one of the three patients who underwent MRI. In two patients MRI was repeated 3 years after the onset, showing marked reduction in abnormal signal; and all the lesions gave low signal on both T1- and T2-weighted images. Bilateral thalamic involvement, especially haemorrhagic, may be considered characteristic of Japanese encephalitis, especially in endemic areas. (orig.)

  1. A Prospective Multi-Center Clinical Trial to Compare Efficiency, Accuracy and Safety Of the VisionScope Imaging System Compared to MRI and Diagnostic Arthroscopy

    Science.gov (United States)

    Xerogeanes, John W.; Safran, Marc R.; Huber, Bryan; Mandelbaum, Bert R.; Robertson, William; Gambardella, Ralph A.

    2014-01-01

    Objectives: Until now, arthroscopic surgery has been the gold standard for the diagnosis of intra-articular pathology. When a patient presents with ongoing pain and/or disability despite non-operative care, MRI is commonly used as a diagnostic modality. To date, there is not a minimally-invasive option that can provide detailed information about the intra-articular pathology of a joint. VisionScope Imaging (VSI) is an office-based diagnostic modality that provides comprehensive real-time images and video of a joint with higher accuracy and reliability compared to static MR images. The purpose of this study was to compare the efficacy, accuracy and safety of VSI compared to MRI and surgical diagnostic arthroscopy. Methods: A prospective, blinded, multi-centered study was performed of all patients who had a routine surgical arthroscopy at one of the six participating clinical sites between July 2012 and May 2013. Patients were consented by the physician investigator at each site. Study inclusion criteria consisted of: suspected meniscal tears or articular cartilage damage. Patients were excluded from the study if they had (1) acute traumatic hemarthoses, (2) concomitant ligament injury, (3) active systemic infection, (4) allergy to silicone or any medication used during the procedure,. All patients had a MRI and a comprehensive physical exam prior to their surgical arthroscopy. Each patient underwent a MRI, VSI exam and surgical diagnostic arthroscopy. The attending physician completed standard forms comparing the VSI exam findings to the diagnostic arthroscopy findings on each patient. Two blinded experts unaffiliated with the study reviewed the VSI and MRI images. The arthroscopy served as the “control” comparison between the VSI and MRI findings. Results: There were 110 patients included in this study. The accuracy, sensitivity and specificity of VSI was equivalent to surgical diagnostic arthroscopy and more accurate than MRI (Table 1). When comparing VSI to

  2. An Automated Mouse Tail Vascular Access System by Vision and Pressure Feedback.

    Science.gov (United States)

    Chang, Yen-Chi; Berry-Pusey, Brittany; Yasin, Rashid; Vu, Nam; Maraglia, Brandon; Chatziioannou, Arion X; Tsao, Tsu-Chin

    2015-08-01

    This paper develops an automated vascular access system (A-VAS) with novel vision-based vein and needle detection methods and real-time pressure feedback for murine drug delivery. Mouse tail vein injection is a routine but critical step for preclinical imaging applications. Due to the small vein diameter and external disturbances such as tail hair, pigmentation, and scales, identifying vein location is difficult and manual injections usually result in poor repeatability. To improve the injection accuracy, consistency, safety, and processing time, A-VAS was developed to overcome difficulties in vein detection noise rejection, robustness in needle tracking, and visual servoing integration with the mechatronics system.

  3. Adaptive radio resource allocation for multiple traffic OFDMA broadband wireless access system

    Institute of Scientific and Technical Information of China (English)

    LU Yan-hui; LUO Tao; YIN Chang-chuan; YUE Guang-xin

    2006-01-01

    In this article, an adaptive radio resource allocation algorithm applied to multiple traffic orthogonal frequency division multiple access (OFDMA) system is proposed, which distributes subcarriers and bits among users according to their different quality of service requirements and traffic type. By classifying and prioritizing the users based on their traffic characteristic and ensuring resource for higher priority users, the new scheme decreases tremendously the outage probability of the users requiting a real-time transmission without impact on the spectrum efficiency of system, as well as the outage probability of data users is not increased compared with the radio resource allocation methods published.

  4. Analysis and Simulation for Capacity of Time Division-Synchronous Code Division Multiple Access System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Capacity both in uplink and downlink of TD-SCDMA (time division-synchronous code division multiple access)system is studied in a multi-cell environment. The theoretical expressions of the mean of intercell interference in uplinkand the mean of sum of power allocation in downlink are given, by which uplink and downlink capacity is analyzed.Furthermore, we give the simulation models for both uplink and downlink capacity. The results from theoretical analysisand simulation fit very well. In the end, the maximum number of users that TD-SCDMA system can serve for 12.2kspeech service is given.

  5. The FODA-TDMA satellite access scheme - Presentation, study of the system, and results

    Science.gov (United States)

    Celandroni, Nedo; Ferro, Erina

    1991-12-01

    A description is given of FODA-TDMA, a satellite access scheme designed for mixed traffic. The study of the system is presented and the choice of some parameters is justified. A simplified analytic solution is found, describing the steady-state behavior of the system. Some results of the simulation tests for an already existing hardware environment are also presented for the channel speeds of 2 and 8 Mb/s, considering both the stationary and the transient cases. The results of the experimentation at 2 Mb/s on the satellite Eutelsat-F2 are also presented and compared with the results of the simulation.

  6. Design and performance evaluation of a wideband FM spread-spectrum multiple-access system

    Science.gov (United States)

    Wachsman, R. H.; Ghais, A. F.

    1971-01-01

    The system described performs the tracking and communications functions of a tracking and data relay satellite system (TDRS). The spread-spectrum signal format is achieved through wide deviation FM by a sinusoidal subcarrier unique to each multiple-access user. A compound phase-locked loop tracks carrier and subcarrier and demodulates data and ranging signals. Design parameters of user and ground terminals for TDRS are given. Acquisition procedures are described. Performance analyses are presented including the effects of noise, RFI, multipath and other users.

  7. The Model and Control Methods of Access to Information and Technology Resources of Automated Control Systems in Water Supply Industry

    Science.gov (United States)

    Rytov, M. Yu; Spichyack, S. A.; Fedorov, V. P.; Petreshin, D. I.

    2017-01-01

    The paper describes a formalized control model of access to information and technological resources of automated control systems at water supply enterprises. The given model considers the availability of various communication links with information systems and technological equipment. There are also studied control methods of access to information and technological resources of automated control systems at water supply enterprises. On the basis of the formalized control model and appropriate methods there was developed a software-hardware complex for rapid access to information and technological resources of automated control systems, which contains an administrator’s automated workplace and ultimate users.

  8. Access Denied

    Science.gov (United States)

    Villano, Matt

    2008-01-01

    Building access control (BAC)--a catchall phrase to describe the systems that control access to facilities across campus--has traditionally been handled with remarkably low-tech solutions: (1) manual locks; (2) electronic locks; and (3) ID cards with magnetic strips. Recent improvements have included smart cards and keyless solutions that make use…

  9. Power and Channel Allocation for Non-orthogonal Multiple Access in 5G Systems: Tractability and Computation

    OpenAIRE

    Lei, Lei; Yuan, Di; Ho, Chin Keong; Sun, Sumei

    2016-01-01

    Network capacity calls for significant increase for 5G cellular systems. A promising multi-user access scheme, non-orthogonal multiple access (NOMA) with successive interference cancellation (SIC), is currently under consideration. In NOMA, spectrum efficiency is improved by allowing more than one user to simultaneously access the same frequency-time resource and separating multi-user signals by SIC at the receiver. These render resource allocation and optimization in NOMA different from orth...

  10. Towards the Adoption of Open Source and Open Access Electronic Health Record Systems

    Directory of Open Access Journals (Sweden)

    Ilias Maglogiannis

    2012-01-01

    Full Text Available As the Electronic Health Record (EHR systems constantly expand to support more clinical activities and their implementations in healthcare organizations become more widespread, several communities have been working intensively for several years to develop open access and open source EHR software, aiming at reducing the costs of EHR deployment and maintenance. In this paper, we describe and evaluate the most popular open source electronic medical records such as openEMR, openMRS and patientOS, providing their technical features and potentials. These systems are considered quite important due to their prevalence. The article presents the key features of each system and outlines the advantages and problems of Open Source Software (OSS Systems through a review of the literature, in order to demonstrate the possibility of their adoption in modern electronic healthcare systems. Also discussed are the future trends of OS EHRs in the context of the Personal Health Records and mobile computing paradigm.

  11. U-Access: a web-based system for routing pedestrians of differing abilities

    Science.gov (United States)

    Sobek, Adam D.; Miller, Harvey J.

    2006-09-01

    For most people, traveling through urban and built environments is straightforward. However, for people with physical disabilities, even a short trip can be difficult and perhaps impossible. This paper provides the design and implementation of a web-based system for the routing and prescriptive analysis of pedestrians with different physical abilities within built environments. U-Access, as a routing tool, provides pedestrians with the shortest feasible route with respect to one of three differing ability levels, namely, peripatetic (unaided mobility), aided mobility (mobility with the help of a cane, walker or crutches) and wheelchair users. U-Access is also an analytical tool that can help identify obstacles in built environments that create routing discrepancies among pedestrians with different physical abilities. This paper discusses the system design, including database, algorithm and interface specifications, and technologies for efficiently delivering results through the World Wide Web (WWW). This paper also provides an illustrative example of a routing problem and an analytical evaluation of the existing infrastructure which identifies the obstacles that pose the greatest discrepancies between physical ability levels. U-Access was evaluated by wheelchair users and route experts from the Center for Disability Services at The University of Utah, USA.

  12. Development of Environmental Decision Support System: Unifying Cross-Discipline Data Access Through Open Source Tools

    Science.gov (United States)

    Freeman, S.; Darmenova, K.; Higgins, G. J.; Apling, D.

    2012-12-01

    A common theme when it comes to accessing climate and environmental datasets is that it can be difficult to answer the five basic questions: Who, What, When, Where, and Why. Sometimes even the act of locating a data set or determining how it was generated can prove difficult. It is even more challenging for non-scientific individuals such as planners and policy makers who need to access and include such information in their work. Our Environmental Decision Support System (EDSS) attempts to address this issue by integrating several open source packages to create a simple yet robust web application for conglomerating, searching, viewing, and downloading environmental information for both scientists and decision makers alike. The system is comprised of several open source components, each playing an important role in the EDSS. The Geoportal web application provides an intuitive interface for searching and managing metadata ingested from data sets/data sources. The GeoServer and ncWMS web applications provide overlays and information for visual presentations of the data through web mapping services (WMS) by ingesting ESRI shapefiles, NetCDF, and HDF files. Users of the EDSS can browse the catalog of available products, enter a simple search string, or even constrain searches by temporal and spatial extents. Combined with a custom visualization web application, the EDSS provides a simple yet efficient means for users to not only access and manipulate climate and environmental data, but also trace the data source and the analytical methods used in the final decision aids products.

  13. Low Access Delay Anti-Collision Algorithm for Reader in RFID systems

    DEFF Research Database (Denmark)

    Galiotto, Carlo; Marchetti, Nicola; Prasad, Neeli R.

    2010-01-01

    Radio Frequency Identification (RFID) is a technology which is spreading more and more as a medium to identify, locate and track assets through the productive chain. As all the wireless communication devices sharing the same transmission channel, RFID readers and tags experience collisions whenever...... deployed over the same area. In this work, the RFID reader collision problem is studied and a centralized scheduling-based algorithm is proposed as possible candidate solution, especially for those scenarios involving static or low mobility readers. Taking into account the circuitry limitations of the tags......, which do not allow to use frequency or code division multiple access schemes in the RFID systems, this paper proposes an algorithm aiming to prevent the readers collisions, while keeping the access delay of the readers to the channel possibly low. The simulation results show that this algorithm performs...

  14. Low Access Delay Anti-Collision Algorithm for Reader in RFID systems

    DEFF Research Database (Denmark)

    Galiotto, Carlo; Marchetti, Nicola; Prasad, Neeli R.

    2010-01-01

    Radio Frequency Identification (RFID) is a technology which is spreading more and more as a medium to identify, locate and track assets through the productive chain. As all the wireless communication devices sharing the same transmission channel, RFID readers and tags experience collisions whenever...... deployed over the same area. In this work, the RFID reader collision problem is studied and a centralized scheduling-based algorithm is proposed as possible candidate solution, especially for those scenarios involving static or low mobility readers. Taking into account the circuitry limitations of the tags......, which do not allow to use frequency or code division multiple access schemes in the RFID systems, this paper proposes an algorithm aiming to prevent the readers collisions, while keeping the access delay of the readers to the channel possibly low. The simulation results show that this algorithm performs...

  15. A practical MRI grading system for osteoarthritis of the knee: Association with Kellgren–Lawrence radiographic scores

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hee-Jin, E-mail: parkhiji@gmail.com [Department of Radiology, Sungkyunkwan University School of Medicine, Kangbuk Samsung Hospital, #108 Pyung-dong, Jongno-gu, Seoul 110-746 (Korea, Republic of); Department of Radiology, Kangwon National University School of Medicine, Baengnyeong-ro 156, Chuncheon-Si, Gangwon-Do Kangwon National University Hospital 200-722 (Korea, Republic of); Kim, Sam Soo, E-mail: samskim@kangwon.ac.kr [Department of Radiology, Kangwon National University School of Medicine, Baengnyeong-ro 156, Chuncheon-Si, Gangwon-Do Kangwon National University Hospital 200-722 (Korea, Republic of); Lee, So-Yeon, E-mail: parkhiji@kwandong.ac.kr [Department of Radiology, Sungkyunkwan University School of Medicine, Kangbuk Samsung Hospital, #108 Pyung-dong, Jongno-gu, Seoul 110-746 (Korea, Republic of); Park, Noh-Hyuck, E-mail: nhpark904@kwandong.ac.kr [Department of Radiology, Myongji Hospital, Kwandong University, College of Medicine, 697-24 Hwajung-dong, Dukyang-ku, Koyang, Kyunggi 412-270 (Korea, Republic of); Park, Ji-Yeon, E-mail: zzzz3@hanmail.net [Department of Radiology, Myongji Hospital, Kwandong University, College of Medicine, 697-24 Hwajung-dong, Dukyang-ku, Koyang, Kyunggi 412-270 (Korea, Republic of); Choi, Yoon-Jung, E-mail: yoonchoi99@gmail.com [Department of Radiology, Sungkyunkwan University School of Medicine, Kangbuk Samsung Hospital, #108 Pyung-dong, Jongno-gu, Seoul 110-746 (Korea, Republic of); Jeon, Hyun-Jun, E-mail: ostrich-13@hanmail.net [Department of Occupational Medicine, Dongsan Medical Center, Keimyung University School of Medicine, 194 Dongsan-Dong, Jung-ku, Taegu (Korea, Republic of)

    2013-01-15

    Purpose: To propose a reproducible and constant MR grading system for osteoarthritis of the knee joint that provides high interobserver and intraoberver agreement and that does not require complicated calculation procedures. Materials and methods: This retrospective study sample included 44 men and 65 women who underwent both MRI and plain radiography of the knee at our institution. All patients were older than 50 years of age (mean 57.7) and had clinically suspected osteoarthritis of the knee. The standard of 4 grades on the MR grade scale was based mainly on cartilage injury and additional findings. Kellgren–Lawrence grades were assessed for the same patient group. The relationship between the results was determined. Statistical analyses were performed including kappa statistics, categorical regression analysis and nonparametric correlation analysis. Results: The interobserver and intraoberver agreements between the two readers in the grading of osteoarthritis were found to be almost perfect. Interobserver and intraobserver agreements were slightly lower for the MR grading system than for the Kellgren–Lawrence grading scale. The correlation between the MR grade and Kellgren–Lawrence grade was very high and did not differ with patient age. The MR grades were highly correlated with the Kellgren–Lawrence grades and showed excellent interobserver and intraobserver agreements. Conclusion: This new MR grading system for osteoarthritis of the knee joint is reproducible and may be helpful for the grading of osteoarthritis of the knee without requiring reference to plain radiography.

  16. Neural Response during the Activation of the Attachment System in Patients with Borderline Personality Disorder: An fMRI Study.

    Science.gov (United States)

    Buchheim, Anna; Erk, Susanne; George, Carol; Kächele, Horst; Martius, Philipp; Pokorny, Dan; Spitzer, Manfred; Walter, Henrik

    2016-01-01

    Individuals with borderline personality disorder (BPD) are characterized by emotional instability, impaired emotion regulation and unresolved attachment patterns associated with abusive childhood experiences. We investigated the neural response during the activation of the attachment system in BPD patients compared to healthy controls using functional magnetic resonance imaging (fMRI). Eleven female patients with BPD without posttraumatic stress disorder (PTSD) and 17 healthy female controls matched for age and education were telling stories in the scanner in response to the Adult Attachment Projective Picture System (AAP), an eight-picture set assessment of adult attachment. The picture set includes theoretically-derived attachment scenes, such as separation, death, threat and potential abuse. The picture presentation order is designed to gradually increase the activation of the attachment system. Each picture stimulus was presented for 2 min. Analyses examine group differences in attachment classifications and neural activation patterns over the course of the task. Unresolved attachment was associated with increasing amygdala activation over the course of the attachment task in patients as well as controls. Unresolved controls, but not patients, showed activation in the right dorsolateral prefrontal cortex (DLPFC) and the rostral cingulate zone (RCZ). We interpret this as a neural signature of BPD patients' inability to exert top-down control under conditions of attachment distress. These findings point to possible neural mechanisms for underlying affective dysregulation in BPD in the context of attachment trauma and fear.

  17. Neural Response during the Activation of the Attachment System in Patients with Borderline Personality Disorder: An fMRI Study

    Science.gov (United States)

    Buchheim, Anna; Erk, Susanne; George, Carol; Kächele, Horst; Martius, Philipp; Pokorny, Dan; Spitzer, Manfred; Walter, Henrik

    2016-01-01

    Individuals with borderline personality disorder (BPD) are characterized by emotional instability, impaired emotion regulation and unresolved attachment patterns associated with abusive childhood experiences. We investigated the neural response during the activation of the attachment system in BPD patients compared to healthy controls using functional magnetic resonance imaging (fMRI). Eleven female patients with BPD without posttraumatic stress disorder (PTSD) and 17 healthy female controls matched for age and education were telling stories in the scanner in response to the Adult Attachment Projective Picture System (AAP), an eight-picture set assessment of adult attachment. The picture set includes theoretically-derived attachment scenes, such as separation, death, threat and potential abuse. The picture presentation order is designed to gradually increase the activation of the attachment system. Each picture stimulus was presented for 2 min. Analyses examine group differences in attachment classifications and neural activation patterns over the course of the task. Unresolved attachment was associated with increasing amygdala activation over the course of the attachment task in patients as well as controls. Unresolved controls, but not patients, showed activation in the right dorsolateral prefrontal cortex (DLPFC) and the rostral cingulate zone (RCZ). We interpret this as a neural signature of BPD patients’ inability to exert top-down control under conditions of attachment distress. These findings point to possible neural mechanisms for underlying affective dysregulation in BPD in the context of attachment trauma and fear. PMID:27531977

  18. MRI features of ventricular system tuberculosis%脑室系统结核的磁共振表现

    Institute of Scientific and Technical Information of China (English)

    毛海霞; 朱慧媛; 王亚丽; 杨洋; 尤小芳; 孙希文

    2016-01-01

    目的 探讨脑室系统结核病患者的头颅MRI表现.方法 回顾性分析并总结我院2009年3月至2014年9月收治的19例脑室系统结核病患者的临床特征及头颅MRI表现.结果 19例脑室系统结核病患者中,男13例,女6例;年龄15 ~81岁,平均(37±16)岁.8例为脑室内结核(5例为脑室内长条状或不规则状结核灶,3例为脑室内结核瘤),6例为结核性室管膜炎,5例为脑室内结核并室管膜炎;14例病变位于侧脑室(13例位于中后部,9例合并结核性脑膜炎,10例合并脑实质结核),5例病变位于第四脑室(5例合并结核性脑膜炎,4例合并脑积水);4例环形强化,15例不均匀强化;10例病灶周围水肿.结论 脑室系统结核病较少见,诊断有一定难度,但其发病部位、MRI信号特点、强化方式及伴发症等表现有一定的特异性,可为脑室系统结核病的诊断提供参考.%Objective To study the MRI features of ventricular system tuberculosis.Methods Nineteen patients with ventricular system tuberculosis in our hospital from Mar.2009 to Sep.2014 were retrospectively identified.Their clinical features and cranial MRI characteristics were reviewed.Results There were 13 males and 6 females,aged from 15-81 years (mean 37 ± 16).Eight patients had intraventricular tuberculosis,with 5 long striped or irregular shaped intraventricular tuberculosis and 3 with ventricular tuberculoma.Six patients had tubercular ependymitis and 5 had intraventricular tuberculosis along with tubercular ependymitis.The lesions of 14 patients were in the lateral ventricle;13 in occipital or temporal horn of lateral ventricle,9 complicated by tubercular meningitis,and 10 complicated by brain tuberculoma.The lesion of 5 patients were in the fourth ventricle,5 in the postmedian of the fourth ventricle,5 complicated by tubercular meningitis and 4 complicated by hydrocephalus.There were 4 cases with ring-enhancement and 15 with heterogeneous enhancement.Ten cases were

  19. Accessibility needs and challenges of a mHealth system for patients with dexterity impairments.

    Science.gov (United States)

    Yu, Daihua X; Parmanto, Bambang; Dicianno, Brad E; Watzlaf, Valerie J; Seelman, Katherine D

    2017-01-01

    Purpose State: An innovative mobile health system called iMHere (interactive Mobile Health and Rehabilitation) has been developed at the University of Pittsburgh to support self-care and adherence to self-care regimens for patients with chronic conditions. The goal of this study is to explore and to identify the accessibility needs and preferences of individuals with dexterity impairments when they use the iMHere system. Participants were asked to perform tasks after a one-week field trial. The time for a participant to complete each task, the number of possible errors a participant made and the number of errors a participant was able to self-correct were recorded and analyzed. The Telehealth Usability Questionnaire was collected to rate participants' experiences. Nine participants with various levels of dexterity abilities were included in the study. A statistically significant negative correlation was identified between participants' dexterity levels and their error ratios by using a Pearson product-moment correlation (r = -0.434, n = 36, p = 0.004). Approximately 51% of errors detected was self-corrected without any help, but other errors called for resolution from a researcher. Due to the diversity of participants' dexterity impairments, their needs and preferences differ one from another. Personalized design may be the key to approaching these challenges in improving accessibility. Implications for Rehabilitation An innovative mobile health system called iMHere has been developed to support self-care and adherence to self-care regimens as part of rehabilitation for patients with chronic conditions. Before populations with these limitations can harness the potential of mHealth, accessibility of mHealth has to be addressed to ensure its quality and value. Dexterity limitations are commonly associated with chronic disease, accidents or aging. The study presented here identified the potential issues and barriers to accessibility related to user

  20. Hybrid mathematical and rule-based system for transmission network planning in open access schemes

    Energy Technology Data Exchange (ETDEWEB)

    Kandil, M. S. [Electrical Department, Mansura University, (Egypt); EI-Debeiky, S. M. [Electrical Department, Ain Shams University, (Egypt); Hasanien, N. E. [Egyptian Electricity Authority, Studies and Researches Department, (Egypt)

    2001-09-01

    The paper presents a planning methodology using an application of a mathematical and a rule-based expert system (ES) to expand the transmission network in open access schemes. In this methodology, the ES suggests a realistic set of generation additions with proper economic signals to the participants, before proceeding with the transmission expansion. A feasible list of transmission alternatives is then assumed to accommodate the proposals for generation. A mathematical method is performed based on marginal cost allocation to optimise the location for the new generation and its transmission expansion scheme simultaneously for each alternative. The optimum alternative, which minimises the overall system's cost function and satisfies the future demand under different operating conditions, is obtained. The ES interacts with the power system planning tools to produce the optimum expansion plan. A practical application is given to demonstrate the effectiveness of the developed prototype system. (Author)

  1. A Frequency—Diversity Spread—Spectrum Multiple Access System with Random Signature Sequences

    Institute of Scientific and Technical Information of China (English)

    CaoYewen; XiangHaige

    1995-01-01

    A new scheme for the spread-spectrum multiple access system named Frequency-Diver-sity Spread-Spectrum Multiple Access(FD-DDMA)system,is proposed.In this FD-SSMA sys-tem,the same information will be modulated on a group of mutually orthogonal frequency compo-nents(carriers)with a random signature sequence at the same time,and it will be demodulated by a coherent receiver for every component and then incorporated (ad if using frequency diversity)on the basis of this random sequence.The spectrum of the modulated signal is very close to that of a white-noise in a wider frequency band due to orthogonality for all frequency components and prop-erty of the random sequence,the system becomes a spread-spectrum one.The (Inverse)Fast Froier Transform(IFFT,FFT)can be applied in the system ,which provides additional flexibility.The performance in an asynchronous mode,such as ability of multiusers,anti-interferences ,is an-alyzed.

  2. Remote access to an interferometric fringes stabilization active system via RENATA

    Science.gov (United States)

    Espitia-Gómez, Javier; Ángel-Toro, Luciano

    2013-11-01

    The Advanced Technology National Network (RENATA, for its acronym in Spanish) is a Colombian, collaborative work tool, linked to other networks worldwide, in which take participation researchers, teachers and students, by sharing laboratory resources located in different universities, institutes and research centers throughout the country. In the Universidad EAFIT (Medellín, Colombia) it has been designed an interferometric fringes stabilization active system, which can be accessed remotely via the RENATA network. A Mach-Zehnder interferometer was implemented, with independent piezoelectric actuators in each arm, with which the lengths of optical path of light that goes over in each of them can be modified. Using these actuators, one can simultaneously perturb the system and compensate the phase differences caused by that perturbation. This allows us to experiment with different disturbs, and analyze the system response to each one of them. This can be made from any location worldwide, and especially from those regions in which optical and optoelectronic components required for the implementation of the interferometer or for the stabilization system are not available. The device can also be used as a platform in order to conduct diverse experiments, involving optical and controlling aspects, constituting with this in a pedagogic tool. For the future, it can be predicted that remote access to available applications would be possible, as well as modifications of the implemented code in labVIEW™, so that researchers and teachers can adapt and improve their functionalities or develop new applications, based on the collaborative work.

  3. Vote-by-Phone: An Investigation of a Usable and Accessible IVR Voting System

    Directory of Open Access Journals (Sweden)

    Danae Holmes

    2016-11-01

    Full Text Available One of the main goals of the Help America Vote Act (HAVA was to ensure that voters with disabilities could vote privately and independently. However, the current state of most voting methods does not allow for private and independent voting for everyone. In response to this issue, we tested a remote IVR voting system developed by Author 1 and Author 2 (2013, with an added audio speed adjustment feature and synthetic voice to increase usability and accessibility, especially for visually impaired voters (Pinter, 2011. The focus of this research was to examine the viability and usability of the IVR voting system as an accessible voting platform for visually impaired voters. The system was tested by users with and without visual impairments, and usability was measured using the three ISO 9241-11 usability metrics (ISO 9241-11, 1998 of efficiency (time to complete a ballot, effectiveness (accuracy, and satisfaction (subjective usability. Results indicate that the IVR voting system could be a viable voting alternative to other established voting methods, with similar performance among sighted and visually impaired users.

  4. Access to the energy system network simulator (ESNS), via remote computer terminals. [BNL CDC 7600/6600 computer facility

    Energy Technology Data Exchange (ETDEWEB)

    Reisman, A W

    1976-08-15

    The Energy System Network Simulator (ESNS) flow model is installed on the Brookhaven National Laboratory (BNL) CDC 7600/6600 computer facility for access by off-site users. The method of access available to outside users is through a system called CDC-INTERCOM, which allows communication between the BNL machines and remote teletype terminals. This write-up gives a brief description of INTERCOM for users unfamiliar with this system and a step-by-step guide to using INTERCOM in order to access ESNS.

  5. P型多系统萎缩的MRI表现%MRI Features of Multiple System Atrophy P Type

    Institute of Scientific and Technical Information of China (English)

    邝岚琼; 王小宜; 邢妩; 廖伟华; 谢芳芳; 那伟

    2012-01-01

    Objective To analyze the MRI features of the multiple system atrophy ( MSA) P,in order to provide ima-geology basis for clinical diagnosis. Materials and Methods MRI findings in 9 patients with MSA P type( parkinsonism in dominant multiple system atrophy) in XiangYa Hospital were analyzed retrospectively. Results Of 9 patients, 6 had abnormal findings in putamen, 4 had putamen atrophy, 2 had the long T2 signal of the putamen edge ( fissure sign) , and 3 had the putamen diffuse little long T1 & T2 signals, and 4 had the very long T, & very short T2 signals in outer back of putamen. Moreover, among these 6 patients, there was one case merely featured in the putamen atrophy and one in the very long T1 & very short T2 signal in the outer back of putamen, and the other 4 cases were found the abnormal changes in a variety of core shell overlap there. There were 5 cases of brain stem abnormalities, one with cross sign, and four with the whole brain stem atrophy (two were found the little long T1 & T2 signal concerning symmetry of the cerebellum feet). Hemisphere abnormalities were found in 3 cases, 3 cases of them were the atrophy of both bilateral frontal temporal parietal oc-cipitals, 2 cases atrophy of bilateral frontal lobes. Cerebellar hemisphere atrophy was found in two cases. Cross sign was found in late MSA P type,and FLAIR sequences facilitate the detection of abnormal signal. Conclusion MRI facilitates the clinical diagnosis of MSA P type.%目的 分析P型多系统萎缩(multiple system atrophy,MSA)的MRI特征,为临床诊断提供影像学依据.资料与方法 回顾性分析经临床诊断为MSA-P型9例患者的常规MRI资料.结果 9例中,6例壳核有异常发现,其中壳核萎缩4例,壳核边缘长T2信号(裂隙征)2例,壳核弥漫性稍长T1、稍长T2信号3例,壳核后外侧极长T1、极短T2信号4例.6例中,单纯表现为壳核萎缩及壳核后外侧极长T1、极短T2信号各1例,余4例为多种壳核异常改变重叠出现.5例脑

  6. Pneumatically Operated MRI-Compatible Needle Placement Robot for Prostate Interventions.

    Science.gov (United States)

    Fischer, Gregory S; Iordachita, Iulian; Csoma, Csaba; Tokuda, Junichi; Mewes, Philip W; Tempany, Clare M; Hata, Nobuhiko; Fichtinger, Gabor

    2008-06-13

    Magnetic Resonance Imaging (MRI) has potential to be a superior medical imaging modality for guiding and monitoring prostatic interventions. The strong magnetic field prevents the use of conventional mechatronics and the confined physical space makes it extremely challenging to access the patient. We have designed a robotic assistant system that overcomes these difficulties and promises safe and reliable intra-prostatic needle placement inside closed high-field MRI scanners. The robot performs needle insertion under real-time 3T MR image guidance; workspace requirements, MR compatibility, and workflow have been evaluated on phantoms. The paper explains the robot mechanism and controller design and presents results of preliminary evaluation of the system.

  7. The Effect of Magnetic Field on Positron Range and Spatial Resolution in an Integrated Whole-Body Time-Of-Flight PET/MRI System.

    Science.gov (United States)

    Huang, Shih-Ying; Savic, Dragana; Yang, Jaewon; Shrestha, Uttam; Seo, Youngho

    2014-11-01

    Simultaneous imaging systems combining positron emission tomography (PET) and magnetic resonance imaging (MRI) have been actively investigated. A PET/MR imaging system (GE Healthcare) comprised of a time-of-flight (TOF) PET system utilizing silicon photomultipliers (SiPMs) and 3-tesla (3T) MRI was recently installed at our institution. The small-ring (60 cm diameter) TOF PET subsystem of this PET/MRI system can generate images with higher spatial resolution compared with conventional PET systems. We have examined theoretically and experimentally the effect of uniform magnetic fields on the spatial resolution for high-energy positron emitters. Positron emitters including (18)F, (124)I, and (68)Ga were simulated in water using the Geant4 Monte Carlo toolkit in the presence of a uniform magnetic field (0, 3, and 7 Tesla). The positron annihilation position was tracked to determine the 3D spatial distribution of the 511-keV gammy ray emission. The full-width at tenth maximum (FWTM) of the positron point spread function (PSF) was determined. Experimentally, (18)F and (68)Ga line source phantoms in air and water were imaged with an investigational PET/MRI system and a PET/CT system to investigate the effect of magnetic field on the spatial resolution of PET. The full-width half maximum (FWHM) of the line spread function (LSF) from the line source was determined as the system spatial resolution. Simulations and experimental results show that the in-plane spatial resolution was slightly improved at field strength as low as 3 Tesla, especially when resolving signal from high-energy positron emitters in the air-tissue boundary.

  8. Modulation of the visual word retrieval system in writing: a functional MRI study on the Japanese orthographies.

    Science.gov (United States)

    Nakamura, Kimihiro; Honda, Manabu; Hirano, Shigeru; Oga, Tatsuhide; Sawamoto, Nobukatsu; Hanakawa, Takashi; Inoue, Hiroshi; Ito, Jin; Matsuda, Tetsu; Fukuyama, Hidenao; Shibasaki, Hiroshi

    2002-01-01

    We used functional magnetic resonance imaging (fMRI) to examine whether the act of writing involves different neuropsychological mechanisms between the two script systems of the Japanese language: kanji (ideogram) and kana (phonogram). The main experiments employed a 2 x 2 factorial design that comprised writing-to-dictation and visual mental recall for kanji and kana. For both scripts, the actual writing produced a widespread fronto-parietal activation in the left hemisphere. Especially, writing of kanji activated the left posteroinferior temporal cortex (lPITC), whereas that of kana also yielded a trend of activation in the same area. Mental recall for both scripts activated similarly the left parietotemporal regions including the lPITC. The writing versus mental recall comparison revealed greater activations in the left sensorimotor areas and right cerebellum. The kanji versus kana comparison showed increased responses in the left prefrontal and anterior cingulate areas. Especially, the lPITC showed a significant task-by-script interaction. Two additional control tasks, repetition (REP) and semantic judgment (SJ), activated the bilateral perisylvian areas, but enhanced the lPITC response only weakly. These results suggest that writing of the ideographic and phonographic scripts, although using the largely same cortical regions, each modulates the visual word-retrieval system according to their graphic features. Furthermore, comparisons with two additional tasks indicate that the activity of the lPITC increases especially in expressive language operations regardless of sensory modalities of the input stimulus.

  9. First clinical experience with a dedicated MRI-guided high-intensity focused ultrasound system for breast cancer ablation

    Energy Technology Data Exchange (ETDEWEB)

    Merckel, Laura G.; Knuttel, Floor M.; Peters, Nicky H.G.M.; Mali, Willem P.T.M.; Bosch, Maurice A.A.J. van den [University Medical Center Utrecht, Department of Radiology, HP E 01.132, Utrecht (Netherlands); Deckers, Roel; Moonen, Chrit T.W.; Bartels, Lambertus W. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Dalen, Thijs van [Diakonessenhuis Utrecht, Department of Surgery, Utrecht (Netherlands); Schubert, Gerald [Philips Healthcare, Best (Netherlands); Weits, Teun [Diakonessenhuis Utrecht, Department of Radiology, Utrecht (Netherlands); Diest, Paul J. van [University Medical Center Utrecht, Department of Pathology, Utrecht (Netherlands); Vaessen, Paul H.H.B. [University Medical Center Utrecht, Department of Anesthesiology, Utrecht (Netherlands); Gorp, Joost M.H.H. van [Diakonessenhuis Utrecht, Department of Pathology, Utrecht (Netherlands)

    2016-11-15

    To assess the safety and feasibility of MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation in breast cancer patients using a dedicated breast platform. Patients with early-stage invasive breast cancer underwent partial tumour ablation prior to surgical resection. MR-HIFU ablation was performed using proton resonance frequency shift MR thermometry and an MR-HIFU system specifically designed for breast tumour ablation. The presence and extent of tumour necrosis was assessed by histopathological analysis of the surgical specimen. Pearson correlation coefficients were calculated to assess the relationship between sonication parameters, temperature increase and size of tumour necrosis at histopathology. Ten female patients underwent MR-HIFU treatment. No skin redness or burns were observed in any of the patients. No correlation was found between the applied energy and the temperature increase. In six patients, tumour necrosis was observed with a maximum diameter of 3-11 mm. In these patients, the number of targeted locations was equal to the number of areas with tumour necrosis. A good correlation was found between the applied energy and the size of tumour necrosis at histopathology (Pearson = 0.76, p = 0.002). Our results show that MR-HIFU ablation with the dedicated breast system is safe and results in histopathologically proven tumour necrosis. (orig.)

  10. Systems Change Enhances Access to Family Planning Training and Care Delivery.

    Science.gov (United States)

    Carvajal, Diana N; Khanna, Niharika; Williams, Mozella; Gold, Marji

    2016-09-01

    Long-acting reversible contraceptives (LARCs) are very effective methods of pregnancy prevention. To ensure autonomy over childbearing, women need access to contraception and abortion services. Family physicians can improve access by increasing numbers and locations of trained providers. In 2014, the University of Maryland (UMD) Reproductive Health EDucation In family medicine (RHEDI) program sought to enhance LARC and abortion training by increasing: (1) resident participation in LARC services, (2) resident participation/interest in abortion care, (3) patient access to LARCs and medication abortions (MABs). We used a pre-post framework comparing years 2013 and 2014 with respect to number of resident-provided LARC services, number of residents participating in abortion, and total number of LARCs and MABs provided practice-wide. The setting is an urban residency practice. (1) increased dedicated appointments for LARC and MABs, (2) dedicated appointment scheduler, (3) comprehensive family planning didactics and clinical workshops, (4) faculty-supported Residents for Choice group. 2014: Residents provided substantially more LARC services compared to 2013. Placement increased from 50 to 90, and removals tripled (25 to 73). 2014 site-wide LARC placement also increased (160 versus 98), removals increased (44 in 2013, 106 in 2014). Twelve residents per year are eligible to participate in abortion care. In 2013, two participated: in 2014, 10 participated. MABs provided in 2014 (18) did not change from 2013 (17). The UMD RHEDI program demonstrated that attention to care-provision systems and education enhances resident training and increases patient access to family planning services. Programs with similar goals may find our methods helpful.

  11. Accessibility patterns and community integration among previously homeless adults: a Geographic Information Systems (GIS) approach.

    Science.gov (United States)

    Chan, Dara V; Gopal, Sucharita; Helfrich, Christine A

    2014-11-01

    Although a desired rehabilitation goal, research continues to document that community integration significantly lags behind housing stability success rates for people of a variety of ages who used to be homeless. While accessibility to resources is an environmental factor that may promote or impede integration activity, there has been little empirical investigation into the impact of proximity of community features on resource use and integration. Using a Geographic Information Systems (GIS) approach, the current study examines how accessibility or proximity to community features in Boston, United States related to the types of locations used and the size of an individual's "activity space," or spatial presence in the community. Significant findings include an inverse relationship between activity space size and proximity to the number and type of community features in one's immediate area. Specifically, larger activity spaces were associated with neighborhoods with less community features, and smaller activity spaces corresponded with greater availability of resources within one's immediate area. Activity space size also varied, however, based on proximity to different types of resources, namely transportation and health care. Greater community function, or the ability to navigate and use community resources, was associated with better accessibility and feeling part of the community. Finally, proximity to a greater number of individual identified preferred community features was associated with better social integration. The current study suggests the ongoing challenges of successful integration may vary not just based on accessibility to, but relative importance of, specific community features and affinity with one's surroundings. Community integration researchers and housing providers may need to attend to the meaning attached to resources, not just presence or use in the community.

  12. Battlefield MRI

    Energy Technology Data Exchange (ETDEWEB)

    Espy, Michelle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-01

    Magnetic Resonance Imaging is the best method for non-invasive imaging of soft tissue anatomy, saving countless lives each year. It is regarded as the gold standard for diagnosis of mild to moderate traumatic brain injuries. Furthermore, conventional MRI relies on very high, fixed strength magnetic fields (> 1.5 T) with parts-per-million homogeneity, which requires very large and expensive magnets.

  13. National Geothermal Data System (USA): an Exemplar of Open Access to Data

    Science.gov (United States)

    Allison, M. Lee; Richard, Stephen; Blackman, Harold; Anderson, Arlene; Patten, Kim

    2014-05-01

    The National Geothermal Data System's (NGDS - www.geothermaldata.org) formal launch in April, 2014 will provide open access to millions of data records, sharing -relevant geoscience and longer term to land use data to propel geothermal development and production. NGDS serves information from all of the U.S. Department of Energy's sponsored development and research projects and geologic data from all 50 states, using free and open source software. This interactive online system is opening new exploration opportunities and potentially shortening project development by making data easily discoverable, accessible, and interoperable. We continue to populate our prototype functional data system with multiple data nodes and nationwide data online and available to the public. Data from state geological surveys and partners includes more than 6 million records online, including 1.72 million well headers (oil and gas, water, geothermal), 670,000 well logs, and 497,000 borehole temperatures and is growing rapidly. There are over 312 interoperable Web services and another 106 WMS (Web Map Services) registered in the system as of January, 2014. Companion projects run by Southern Methodist University and U.S. Geological Survey (USGS) are adding millions of additional data records. The DOE Geothermal Data Repository, currently hosted on OpenEI, is a system node and clearinghouse for data from hundreds of U.S. DOE-funded geothermal projects. NGDS is built on the US Geoscience Information Network (USGIN) data integration framework, which is a joint undertaking of the USGS and the Association of American State Geologists (AASG). NGDS complies with the White House Executive Order of May 2013, requiring all federal agencies to make their data holdings publicly accessible online in open source, interoperable formats with common core and extensible metadata. The National Geothermal Data System is being designed, built, deployed, and populated primarily with support from the US

  14. Sub-THz photonic frequency conversion using optoelectronic transistors for future fully coherent access network systems

    Science.gov (United States)

    Otsuji, Taiichi; Sugawara, Kenta; Tamamushi, Gen; Dobroiu, Adrian; Suemitsu, Tetsuya; Ryzhii, Victor; Iwatsuki, Katsumi; Kuwano, Shigeru; Kani, Jun-ichi; Terada, Jun

    2016-02-01

    This paper reviews advances in sub-THz photonic frequency conversion using optoelectronic transistors for future fully coherent access network systems. Graphene-channel field effect transistors (G-FETs) and InP-based high electron mobility transistors (inP-HEMT) are experimentally examined as photonic frequency converters. Optoelectronic properties and three-terminal functionalities of the G-FETs and InP-HEMTs are exploited to perform single-chip photonic double-mixing operation over the 120 GHz wireless communication band. A single transistor can photomix the optical subcarriers to generate LO and mix down the RF data on the sub-THz carrier to the IF band.

  15. Improved H_∞ filtering for Markov jumping linear systems with non-accessible mode information

    Institute of Scientific and Technical Information of China (English)

    GUO YaFeng; LI ShaoYuan

    2009-01-01

    This paper is concerned with the H_∞ filtering problems for both continuous-and discrete-time Markov jumping linear systems (MJLS) with non-accessible mode Information.A new design method is proposed,which greatly reduces the overdesign Introduced in the derivation process.The desired filters can be obtained from the solution of convex optimization problems in terms of linear matrix inequalities (LMIs),which can be solved via efficient interior-point algorithms.Numerical examples are provided to Illustrate the advantages of the proposed approach.

  16. Measuring access to primary medical care: some examples of the use of geographical information systems.

    Science.gov (United States)

    Parker, E B; Campbell, J L

    1998-06-01

    This paper explores the potential for geographical information system technology in defining some variables influencing the use of primary care medical services. Eighteen general practices in Scotland contributed to a study examining the accessibility of their services and their patients' use of the local Accident and Emergency Department. Geo-referencing of information was carried out through analysis of postcode data relating to practices and patients. This information was analyzed using ARC/INFO GIS software in conjunction with the ORACLE relational database and 1991 census information. The results demonstrate that GIS technology has an important role in defining and analyzing the use of health services by the population.

  17. Design of Nutrition Catering System for Athletes Based on Access Database

    Directory of Open Access Journals (Sweden)

    Hongjiang Wu,

    2015-08-01

    Full Text Available In order to monitor and adjust athletes' dietary nutrition scientifically, Active X Data Object (ADO and Structure Query Language (SQL were used to produce program under the development environment of Visual Basic 6.0 and Access database. The consulting system on food nutrition and dietary had been developed with the two languages combination and organization of the latest nutrition information. Nutrition balance of physiological characteristics, assessment for nutrition intake, inquiring nutrition of common food and recommended of functional nourishing food could be achieved for different events and different level of athletes.

  18. Optical code division multiple access secure communications systems with rapid reconfigurable polarization shift key user code

    Science.gov (United States)

    Gao, Kaiqiang; Wu, Chongqing; Sheng, Xinzhi; Shang, Chao; Liu, Lanlan; Wang, Jian

    2015-09-01

    An optical code division multiple access (OCDMA) secure communications system scheme with rapid reconfigurable polarization shift key (Pol-SK) bipolar user code is proposed and demonstrated. Compared to fix code OCDMA, by constantly changing the user code, the performance of anti-eavesdropping is greatly improved. The Pol-SK OCDMA experiment with a 10 Gchip/s user code and a 1.25 Gb/s user data of payload has been realized, which means this scheme has better tolerance and could be easily realized.

  19. Exploring the drivers of health and healthcare access in Zambian prisons: a health systems approach.

    Science.gov (United States)

    Topp, Stephanie M; Moonga, Clement N; Luo, Nkandu; Kaingu, Michael; Chileshe, Chisela; Magwende, George; Heymann, S Jody; Henostroza, German

    2016-11-01

    Prison populations in sub-Saharan Africa (SSA) experience a high burden of disease and poor access to health care. Although it is generally understood that environmental conditions are dire and contribute to disease spread, evidence of how environmental conditions interact with facility-level social and institutional factors is lacking. This study aimed to unpack the nature of interactions and their influence on health and healthcare access in the Zambian prison setting. We conducted in-depth interviews of a clustered random sample of 79 male prisoners across four prisons, as well as 32 prison officers, policy makers and health care workers. Largely inductive thematic analysis was guided by the concepts of dynamic interaction and emergent behaviour, drawn from the theory of complex adaptive systems. A majority of inmates, as well as facility-based officers reported anxiety linked to overcrowding, sanitation, infectious disease transmission, nutrition and coercion. Due in part to differential wealth of inmates and their support networks on entering prison, and in part to the accumulation of authority and material wealth within prison, we found enormous inequity in the standard of living among prisoners at each site. In the context of such inequities, failure of the Zambian prison system to provide basic necessities (including adequate and appropriate forms of nutrition, or access to quality health care) contributed to high rates of inmate-led and officer-led coercion with direct implications for health and access to healthcare. This systems-oriented analysis provides a more comprehensive picture of the way resource shortages and human interactions within Zambian prisons interact and affect inmate and officer health. While not a panacea, our findings highlight some strategic entry-points for important upstream and downstream reforms including urgent improvement in the availability of human resources for health; strengthening of facility-based health services systems

  20. Power Stabilization Strategy of Random Access Loads in Electric Vehicles Wireless Charging System at Traffic Lights

    Directory of Open Access Journals (Sweden)

    Linlin Tan

    2016-10-01

    Full Text Available An opportunity wireless charging system for electric vehicles when they stop and wait at traffic lights is proposed in this paper. In order to solve the serious power fluctuation caused by random access loads, this study presents a power stabilization strategy based on counting the number of electric vehicles in a designated area, including counting method, power source voltage adjustment strategy and choice of counting points. Firstly, the circuit model of a wireless power system with multi-loads is built and the equation of each load is obtained. Secondly, after the counting method of electric vehicles is stated, the voltage adjustment strategy, based on the number of electric vehicles when the system is at a steady state, is set out. Then, the counting points are chosen according to power curves when the voltage adjustment strategy is adopted. Finally, an experimental prototype is implemented to verify the power stabilization strategy. The experimental results show that, with the application of this strategy, the charging power is stabilized with the fluctuation of no more than 5% when loads access randomly.